https://www.youtube.com/watch?v=ct1U3wTCy3I&ab_channel=%EA%B9%80%EC%A2%85%EC%B2%A0%27%EC%9B%90%ED%8F%AC%EC%9D%B8%ED%8A%B8%EB%A0%88%EC%8A%A8%27



https://www.youtube.com/watch?v=-lnd3vgy4Fs&ab_channel=%EC%A3%BC%EC%8B%9D%ED%88%AC%EC%9E%90%EC%99%80%EC%9A%B0%EB%84%B7 40분짜리 먼저 보고  1시간 30분짜리 보는게 나을듯.....