Hellow guys, Welcome to my website, and you are watching [다시보기] 4월 7일 (금) 오후 사이언스 투데이 / YTN 사이언스. and this vIdeo is uploaded by YTN 사이언스 투데이 at 2023-04-07T02:24:20-07:00. We are pramote this video only for entertainment and educational perpose only. So, I hop you like our website.