R and S Configuration Using Cahn Ingold Prelog Priority Rules Leah Fisch

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  • Опубликовано: 22 янв 2025

Комментарии • 356

  • @dreo149
    @dreo149 8 лет назад +22

    THANK YOU SO MUCH. My professor taught us how to get the R and S for the simplest molecule, then gave us an extremely complicated one for the exam.. I learned more from you in 15 minutes than I did in 2 hours with my prof.

    • @Leah4sci
      @Leah4sci  Год назад +2

      You're very welcome, so happy to help!

  • @Sgtpwnsalot
    @Sgtpwnsalot 5 лет назад +10

    BRO THIS TOPIC WAS ALWAYS CONFUSING BUT YOU JUST BROKE IT DOWN SO EASILY I LOVE YOU

    • @Leah4sci
      @Leah4sci  5 лет назад +1

      Glad you are able to understand the topic well. Don't forget to subscribe! :)

  • @spam035
    @spam035 3 года назад +39

    I must have done some good deed in the past to be able to find your channel. Thank you so much. You are the best chemistry tutor I have ever had the chance to learn from.

    • @Leah4sci
      @Leah4sci  3 года назад +6

      Wow, thank you!

  • @vanastasia8702
    @vanastasia8702 7 лет назад +178

    future pharmacist here. thank you so much!

    • @Leah4sci
      @Leah4sci  7 лет назад +3

      You are welcome :)

    • @mahadihasan7087
      @mahadihasan7087 6 лет назад

      what do u mean

    • @serene9532
      @serene9532 6 лет назад +22

      mahadi hasan this was all pretty straightforward...consult a dictionary if you still don't get it :)

    • @toluwalaseogunsola4972
      @toluwalaseogunsola4972 3 года назад

      Lol same here

    • @derekpenner5052
      @derekpenner5052 Год назад +9

      hi quick check were you able to become a pharmacist?

  • @Evelynsvoice_newgen
    @Evelynsvoice_newgen Год назад +2

    Thank God I found your channel, you videos are literally saving my life, have organic chemistry in two weeks and I am confident I will ace it.

    • @Leah4sci
      @Leah4sci  Год назад

      Always happy to help! If you're pre-studying now and are interested in additional help as you go through the class, make sure to check out my Organic Chemistry Study Hall. Details: leah4sci.com/join or contact me through my website leah4sci.com/contact/

  • @Sal19
    @Sal19 6 лет назад +82

    you could also tell the difference between R and S by the direction of the arrow and connecting it to the way both letters R and S are written .
    when writing R you have to go clockwise (the upper part of it)
    and when writing S you have to go counter clockwise .

  • @AnayaAli-x9z
    @AnayaAli-x9z 3 месяца назад

    Even today, you are saving lives. I might cry because I thought I was dumb, but you really broke it down nicely for me. I don't understand why Ochem professors can't explain it simply like this. Thank you so much.

    • @Leah4sci
      @Leah4sci  3 месяца назад

      it frustrates me so much when the people actually PAID to teach you, throw information at you making you feel like you're dumb because they haven't tried hard enough to convey the information. I'm glad to hear that my videos are showing you the opposite

  • @really_gigi
    @really_gigi 3 года назад +5

    THANK YOU LEAH!!! Wow, please never stop this amazing channel! You are clearly one of the best.

    • @Leah4sci
      @Leah4sci  3 года назад

      You're so welcome! And I have no plans of stopping :)

  • @gumaropedro1927
    @gumaropedro1927 4 года назад +35

    My professor makes this look so hard. So the problem is not the topic but the way some professors teach it.

    • @Leah4sci
      @Leah4sci  4 года назад +9

      Sometimes we need a different take to understand.

  • @gjt4773
    @gjt4773 3 года назад

    I've looked at over 50 of your videos, and I pretty sure you're a genius, at the very least a didactic genius.

    • @Leah4sci
      @Leah4sci  3 года назад

      Oh wow, 50! I'm honored!! and Thanks so much for the kind words, I love teaching and promise to strive to live up to your 'didactic genius' compliment

  • @pasutto-ying847
    @pasutto-ying847 4 года назад +4

    Thank you! I was confused for about an hour, but after seeing your video, I get it now.

    • @Leah4sci
      @Leah4sci  4 года назад +1

      Awesome! Glad it helped!

  • @SnowdropsRivers
    @SnowdropsRivers 8 лет назад +1

    BRILLIANT VIDEO!!!! Never could understand this but you explained it in one video and I understand it now! Woohoo!!!!

  • @arshadarshad-zk8fk
    @arshadarshad-zk8fk 3 года назад +1

    Outstanding explanation of difficult topic!
    Amazing work
    This channel must have millions of subscribers!

    • @Leah4sci
      @Leah4sci  3 года назад +1

      Not yet, but I care about all my subscribers and strive to help the understand (and dare I hope love) orgo!

  • @adilanyosisye2179
    @adilanyosisye2179 3 года назад +3

    Madamme LEAH! You are so much good in Organic Chemistry, You make Hard things in Stereochemistry simple as much a possible, I appreciate You and U always be blessed! Continue by doing so for other courses to help Us enjoy Chemistry or become better Chemists!

    • @Leah4sci
      @Leah4sci  3 года назад

      Wow, thank you! Happy to help!

  • @mursalinbony5716
    @mursalinbony5716 3 месяца назад

    U did very awesome! Absolute genius! I'm facing so much problem with this topic now u cleared me perfectly! Thanks a gallon!

    • @Leah4sci
      @Leah4sci  3 месяца назад

      Awesome, so glad it helped!

  • @zeromotivation1817
    @zeromotivation1817 Год назад +1

    I know this was so long ago, but still. thanks Leah.
    FYI you can always think of it as a steering wheel, pull down to the right to turn right -R
    and the old term for left-handed was sinister.
    pull down on the left to turn left -S

    • @Leah4sci
      @Leah4sci  Год назад

      You're welcome! Great tip for memorization. :)

  • @dannydk6
    @dannydk6 8 лет назад

    This made so much sense. Excellent oratory skills and superb explanations. This was wayyy better than 2 weeks of professor's explanation. Cheers Leah, you're a lifesaver!

    • @Leah4sci
      @Leah4sci  Год назад

      You're so very welcome, happy to help!

  • @jingyiwang5113
    @jingyiwang5113 3 дня назад

    Thank you so much for this clear explanation! It is really useful! It helps a lot!

    • @Leah4sci
      @Leah4sci  2 дня назад

      You're very welcome, I'm so glad it helped!

  • @SurajBadshara
    @SurajBadshara 4 года назад +2

    Your teaching is amazing 🤩

  • @finyuelymndeme148
    @finyuelymndeme148 5 лет назад +1

    You're more than genius, keep it up my madam!!!

  • @watsupman350
    @watsupman350 9 лет назад

    thank you, most simplest and most concise terms of any of the videos i've seen on this topic

  • @Arnavpundir114
    @Arnavpundir114 6 лет назад +1

    Madam you have great explanation you have cleared all my doubts thank you so much

  • @Tech_Ash_Arora
    @Tech_Ash_Arora 7 лет назад +1

    U r Awsm mam. before watching this video R&s to found more difficult for me but now its very easy ...Thank u so much
    🙏🙏🙏🙏🙏

    • @Leah4sci
      @Leah4sci  7 лет назад

      You're very welcome!

  • @gashawtadele772
    @gashawtadele772 7 лет назад

    Thank you so much !! I was learn so many times but,it does not understand about R and S configration before this lesson .But,now it is very clear thank you once again

    • @Leah4sci
      @Leah4sci  7 лет назад

      Glad I could help! You're welcome

  • @MemoryMuzengeza-q2y
    @MemoryMuzengeza-q2y Год назад

    Your teaching is excellent 🦋🥰♥️

  • @RajeshSingh-pn1uy
    @RajeshSingh-pn1uy 8 лет назад +11

    Respect to u from India... U r awsome mam... making it easy for me..

  • @vishallohar7960
    @vishallohar7960 9 лет назад

    Thank you so much even my class teacher won't explained me as easier as you explained...

    • @Leah4sci
      @Leah4sci  Год назад

      You're welcome, I'm so happy to help clear things up for you!

  • @shamatauqeer5813
    @shamatauqeer5813 Месяц назад

    Simple yet amazing way

    • @Leah4sci
      @Leah4sci  Месяц назад

      I hope you found it clear and helpful!

  • @mariajabbour4220
    @mariajabbour4220 8 лет назад +1

    Leah! you're my savior !:) thank you so much for your help! have a great day

    • @Leah4sci
      @Leah4sci  Год назад

      Awww, you're so welcome!

  • @Amani-d1u
    @Amani-d1u 8 лет назад +12

    thanx ...med student in Jordan university

    • @Leah4sci
      @Leah4sci  Год назад

      You're very welcome!

  • @vincentobwora
    @vincentobwora Год назад +1

    Thank you.. i gained much than when i was in class

    • @Leah4sci
      @Leah4sci  Год назад

      I'm so glad that you found the video helpful!

  • @babliohehe3141
    @babliohehe3141 2 года назад +1

    but what will be the priority order if the chiral carbon has a ethyl group and a ethenyl group?

    • @dariapiotrowska9584
      @dariapiotrowska9584 2 года назад

      when there's a multiple binding you double/triple (depending if it's double or triple bond) the number of particles that are connected to the c

    • @Leah4sci
      @Leah4sci  2 года назад

      I'm sorry, but I don't offer tutoring over social media. For help with questions like this and more, I recommend joining the organic chemistry study hall. Details: leah4sci.com/join or contact me through my website leah4sci.com/contact/

  • @alhazimkhan1157
    @alhazimkhan1157 4 года назад

    Your explanation is clear and systematic 👍🏻 Thank You So Much

    • @Leah4sci
      @Leah4sci  4 года назад

      You are welcome!

  • @stephenugochukwu9472
    @stephenugochukwu9472 3 года назад

    Thank you so much, Ms. Leah; I appreciate you.

    • @Leah4sci
      @Leah4sci  3 года назад

      You are so welcome!

  • @Inspiringmedico22
    @Inspiringmedico22 6 лет назад +4

    Love from india .😍...very helpful

    • @Leah4sci
      @Leah4sci  Год назад +1

      Glad it helped!

    • @Inspiringmedico22
      @Inspiringmedico22 Год назад

      5 yrs ago I was preparing for medschool exams and today after I saw your reply I am passed out from med school. Time flies

  • @gabrielclazzer6572
    @gabrielclazzer6572 8 месяцев назад

    Good explanation, Keep it up!

    • @Leah4sci
      @Leah4sci  8 месяцев назад

      Thank you and I'll try :)

  • @KhinSintHan
    @KhinSintHan 3 месяца назад

    So helpful to me thanks a million ❤

    • @Leah4sci
      @Leah4sci  3 месяца назад +1

      Happy to help and you're very welcome!

  • @SyrianSoaper
    @SyrianSoaper Год назад

    the videos keep saying to follow along with the cheat sheet, but each time i try to download the chirality cheat sheet i get a different email with a link that is not the chirality cheat sheet.

    • @Leah4sci
      @Leah4sci  Год назад

      That shouldn't be happening, email me so I can figure out what's going on. Leah4sci.com/contact

  • @selenarivera6945
    @selenarivera6945 3 года назад +1

    Omg thank you so much...so simple and informative

    • @Leah4sci
      @Leah4sci  3 года назад +1

      Glad it was helpful!

  • @ajingobabeofficial1478
    @ajingobabeofficial1478 6 лет назад

    I didn't understand it in class
    But you just made it easier for me
    Love you more😘😘

    • @Leah4sci
      @Leah4sci  6 лет назад

      Glad the video helped you understand the topic better! You are very much welcome!

  • @eman4159
    @eman4159 10 месяцев назад

    you're a life saver ❤❤thank you so much

    • @Leah4sci
      @Leah4sci  10 месяцев назад

      Awww, you're so welcome!

  • @RaiShahJahanK
    @RaiShahJahanK 5 лет назад

    thanks a lot, this was very helpful lecture. i think my professor prepared from your video but did not convey that good. ;-) , once again thanks.

    • @Leah4sci
      @Leah4sci  5 лет назад

      You're very welcome! I'm glad to hear my video made it clearer for you.

  • @CraDejaC
    @CraDejaC 5 лет назад +2

    Literal perfection!

  • @seijillamas4556
    @seijillamas4556 6 лет назад +1

    Thank you very much!!! Your channel was really helpful.

    • @Leah4sci
      @Leah4sci  6 лет назад

      Thanks for visiting. Don't forget to susbscribe!

    • @masu000
      @masu000 4 года назад

      Thankyou mam

  • @sandyabdoni1992
    @sandyabdoni1992 3 года назад

    Amazing explanation!

    • @Leah4sci
      @Leah4sci  3 года назад

      Glad it was helpful!

  • @jennyyyrod
    @jennyyyrod 2 месяца назад

    hi, i know this was posted a while ago, but on the last example, what made you decide to put the Hydrogen in the back?

    • @Leah4sci
      @Leah4sci  2 месяца назад +1

      The hydrogen was invisible in the original line structure of 2-butanol. However, since the OH group was on a wedge, the only position left for that invisible hydrogen to be drawn was on a dash in the back of the structure.

  • @rajatrautela5256
    @rajatrautela5256 5 лет назад

    Thanks mam ,you are doing a great job ,teacher= god 🤗

    • @Leah4sci
      @Leah4sci  5 лет назад +1

      You're welcome ! :)

  • @tejasghag3866
    @tejasghag3866 8 лет назад

    Thanks
    This video helped me to understand r s configuration.....

    • @Leah4sci
      @Leah4sci  Год назад

      You're welcome, happy to help!

  • @tenipham6665
    @tenipham6665 3 года назад

    If they give you a complicated compound and asked you to find the stereo centre, how would you ID them ? For example morphine

    • @Leah4sci
      @Leah4sci  Год назад

      I'm sorry, but I don't offer tutoring over social media. If you ever find you need help with questions like this again, I recommend joining the organic chemistry study hall. Details: leah4sci.com/join or contact me through my website leah4sci.com/contact/

  • @gissellem1341
    @gissellem1341 5 лет назад

    This video was so helpful, thank you so much !

    • @Leah4sci
      @Leah4sci  5 лет назад

      Glad I could help!

  • @phahladiramoja5740
    @phahladiramoja5740 6 лет назад +1

    your videos are amazing thanks a ton.

    • @Leah4sci
      @Leah4sci  5 лет назад

      You're welcome! Glad to help! :)

  • @dineshranawat449
    @dineshranawat449 9 лет назад

    u r just the best.... bless u!!! Leah

  • @Ageze93
    @Ageze93 6 лет назад

    You are awesome! please keep making more videos

    • @Leah4sci
      @Leah4sci  6 лет назад

      Thanks! I sure will! be sure to subscribe to the channel :)

  • @millykangina8872
    @millykangina8872 7 лет назад +1

    Thanx a lot you have made the lesson interesting

  • @thechuggs8997
    @thechuggs8997 3 года назад

    So the ranking is based on atomic mass right? Not reactivity?

    • @Leah4sci
      @Leah4sci  3 года назад

      Neither! atomic number

  • @charlesdale2600
    @charlesdale2600 7 лет назад +1

    Do I have to pay to download your worksheets?

    • @Leah4sci
      @Leah4sci  7 лет назад +1

      Are you referring to the cheat sheets? If so, they are free :)

  • @roopakv3834
    @roopakv3834 6 лет назад

    your videos are really awesome

  • @sarahsejour9765
    @sarahsejour9765 4 года назад

    I love her voice

  • @احمد-نمر
    @احمد-نمر 5 лет назад +1

    Viewer from Arab Republic of Egypt

    • @Leah4sci
      @Leah4sci  5 лет назад

      Awesome! Welcome to my channel!

  • @anujavaidya4982
    @anujavaidya4982 6 лет назад +1

    Great trick..thanks a lot for sharing this🖒

    • @Leah4sci
      @Leah4sci  6 лет назад

      You're welcome! Feel free to share the video/channel :)

  • @mariamrajput1443
    @mariamrajput1443 8 лет назад

    is it necessary to draw fischer projection before assigning configuration?

    • @ahmedshoulah8278
      @ahmedshoulah8278 7 лет назад

      Yes, chan golden perlog system is also important for drowing fisher projuction

    • @Leah4sci
      @Leah4sci  11 месяцев назад

      Not at all. Only draw it if you're asked to, otherwise use the tricks I teach for various conformations to solve for R/S however you see it

  • @Vivek_001
    @Vivek_001 5 лет назад

    What if wedge and dash are not given?just simple lines then what should be done...can R and S be found?

    • @Leah4sci
      @Leah4sci  Год назад

      If not given in 3-D then you have no way of knowing. Meaning, it could be both

    • @Vivek_001
      @Vivek_001 Год назад

      @@Leah4sci Wow!.....was not expecting a reply 3 years later!
      I already gave up on chemistry, still...Thank You. Some of your videos helped me.

  • @ヒョウソウエン
    @ヒョウソウエン 7 месяцев назад

    THANK YOU SOOOO MUCH!! you are my god❤

    • @Leah4sci
      @Leah4sci  7 месяцев назад

      You're very welcome, but just a person, not a god. I don't want to be in control of that much! ;)

  • @lavinarizwani9423
    @lavinarizwani9423 5 лет назад

    you are an idol mam.. loved ur vedios

    • @Leah4sci
      @Leah4sci  5 лет назад

      Glad you've enjoyed them :)

  • @anuradharamnauth9856
    @anuradharamnauth9856 3 года назад

    Thank you so much!!!!!!♥️♥️♥️♥️♥️

    • @Leah4sci
      @Leah4sci  3 года назад +1

      You are so welcome!

  • @bapuraokulkarni1129
    @bapuraokulkarni1129 6 лет назад

    Leah4sci.great explanation

  • @tommyers6782
    @tommyers6782 7 лет назад

    So because of isotopes its BEST TO PRIORITIZE THE NUMBERING USING ATOMIC MASS making it more consistent??????

    • @Leah4sci
      @Leah4sci  7 лет назад

      Yes and no. We use periodic table trend/atomic number for simplicity. If and only if faced with an isotope you'd look at mass. I say this because sometimes an atom will have lower mass than a previous atom (rare) and because it's more confusing to have to look up the mass when most orgo professors do not include them on exams.

    • @tommyers6782
      @tommyers6782 7 лет назад

      Could you please elaborate" I say this because sometimes an atom will have lower mass than a previous atom (rare)" I still don't understand, you only explained that its best to use atomic number, not mass because exams use it and that its confusing but Im not talking about test taking, no offense It just seems to make sense if atomic mass is used to prioritize. Until you explain please

  • @kkn5523
    @kkn5523 6 лет назад

    What if i have a primary carboxylic acid and primary alcohol attached to the chiral carbon?

    • @Leah4sci
      @Leah4sci  6 лет назад

      I'm sorry, but I don't offer tutoring through RUclips comments. For help with this and more, I recommend joining the organic chemistry study hall. Full details: leah4sci.com/join

  • @tuktak835
    @tuktak835 3 года назад

    Perfect thank you! From Germany

    • @Leah4sci
      @Leah4sci  3 года назад +1

      You're welcome!

  • @sambel7132
    @sambel7132 7 лет назад

    that was reaaaly helpful .thank u so much 😍😍

    • @Leah4sci
      @Leah4sci  Год назад

      You're welcome, happy to help!

  • @michelle_xcvii
    @michelle_xcvii 8 лет назад

    Thank you so much. This was super helpful!

    • @Leah4sci
      @Leah4sci  Год назад

      You're so very welcome, happy to help!

  • @ikramrana5859
    @ikramrana5859 7 лет назад

    thank you so much ....i'm addicted to you

    • @Leah4sci
      @Leah4sci  7 лет назад

      Too funny! You are very welcome

  • @अभिषेकआनंद
    @अभिषेकआनंद 4 года назад

    Thank you leah🤗

    • @Leah4sci
      @Leah4sci  4 года назад

      You're very welcome!

  • @RithikRay-ui4pf
    @RithikRay-ui4pf Месяц назад

    Thank youuuu sooo much maammm

    • @Leah4sci
      @Leah4sci  Месяц назад

      you're very welcome!

  • @ciannasinclair5888
    @ciannasinclair5888 3 года назад

    this helped so much omg thank you !!!!

  • @DrHaffeast
    @DrHaffeast 2 года назад

    Good explaination

    • @Leah4sci
      @Leah4sci  2 года назад +1

      Glad you liked it!

  • @larissabts6638
    @larissabts6638 4 года назад

    Really helpful.
    Thanks alot .
    You're amazing

    • @Leah4sci
      @Leah4sci  4 года назад

      You're welcome 😊 Happy to help!

  • @danielnwokeafor6928
    @danielnwokeafor6928 2 года назад

    Please help with naming the compound

    • @Leah4sci
      @Leah4sci  2 года назад

      I'm sorry, but I don't offer tutoring over social media. For help with questions like this and more, I recommend joining the organic chemistry study hall. Details: leah4sci.com/join or contact me through my website leah4sci.com/contact/

  • @exploring197
    @exploring197 5 лет назад

    Can you please make a video on M and P configuration

    • @Leah4sci
      @Leah4sci  Год назад

      I don't know what that is

  • @binujajayaseelan671
    @binujajayaseelan671 7 лет назад +1

    Really helpful and easy to understand

  • @jeffrey3690
    @jeffrey3690 2 года назад

    you said we rank by atomic number in the first few minutes, dont we rank by mass?

    • @Leah4sci
      @Leah4sci  2 года назад

      Yes. One goes hand in hand with the other. As atomic number increases, so does an atom's mass. Bigger/heavier groups, whichever way you want to think of it, take priority.

  • @pettzthatgal2491
    @pettzthatgal2491 8 лет назад

    Thanks a lot..that has really helped me

    • @Leah4sci
      @Leah4sci  Год назад

      You're so very welcome!

  • @madhubabu2511
    @madhubabu2511 8 лет назад +4

    wonderful it's make very easy to understand me soo thanks fisch

  • @ZippyandOllie
    @ZippyandOllie 9 лет назад

    thank you so much Leah!

  • @aderounmuboluwatife4641
    @aderounmuboluwatife4641 3 года назад

    I can't access the book

    • @Leah4sci
      @Leah4sci  3 года назад

      That's strange, I just tried and it's working on my end. Try clearing your cache and sign up for it again. If you still have problems, contact me at leah4sci.com/contact.

  • @armstrongmukonka3379
    @armstrongmukonka3379 4 года назад

    NICE video madam and good luck

    • @Leah4sci
      @Leah4sci  4 года назад

      Thank you very much

  • @khaleelbasha9746
    @khaleelbasha9746 6 лет назад

    tq ....mam u r clear my doubts.

    • @Leah4sci
      @Leah4sci  6 лет назад

      Glad I could help!

  • @arvind3656
    @arvind3656 3 года назад

    Nice video 👍👍👍

  • @lanaloy7880
    @lanaloy7880 9 лет назад +11

    thanks so much
    l love you😘😘😘

    • @Leah4sci
      @Leah4sci  Год назад

      you're very welcome!

  • @anoodalshammari4615
    @anoodalshammari4615 9 лет назад +2

    thank you so much you help me 😢❤️

  • @camjo6397
    @camjo6397 5 лет назад +2

    Why do I remember hearing that you can only determine absolute configuration experimentally?

    • @Leah4sci
      @Leah4sci  Год назад

      Absolute configuration is R/S. Perhaps you're thinking of relative configuration?

  • @بلالغانم-ز6ز
    @بلالغانم-ز6ز 4 года назад

    How wonderful you had been doing as well I'd liked ur style in explication keep going on

    • @Leah4sci
      @Leah4sci  4 года назад

      Thank you, I will :)

  • @ahmedabdulrazzaq1159
    @ahmedabdulrazzaq1159 5 лет назад

    You said there are 4 conditions of #4 but you didn't explain it! .... I want to know the #4 which is not fwd/back . thank you

    • @Leah4sci
      @Leah4sci  5 лет назад

      at which specific point in the video? (Timestamp please)

  • @sicklesword2511
    @sicklesword2511 7 лет назад

    thank you so much!!! helps me a lot!

    • @Leah4sci
      @Leah4sci  6 лет назад

      You are very welcome!

  • @nzubeokafor8405
    @nzubeokafor8405 6 лет назад +2

    God bless you!!!

  • @lamerde6174
    @lamerde6174 6 лет назад

    Thank u so much
    From algeria

    • @Leah4sci
      @Leah4sci  6 лет назад

      You're very welcome!

  • @Frey1468
    @Frey1468 Год назад

    Thankyou so much❤

  • @IAS297
    @IAS297 3 года назад +1

    Thank u Ma'am

    • @Leah4sci
      @Leah4sci  3 года назад +1

      You're welcome 😊

  • @brightonmudenda440
    @brightonmudenda440 Год назад

    Very helpful!!! thank you :)

  • @Shirl33n
    @Shirl33n 4 года назад

    I finally understand, thank you