Hello guys, Welcome to Africa's Largest Video Search Engine, and you are watching 삼각형을 이용한 구조물이 많은 이유는? / YTN 사이언스. and this video is uploaded by YTN 사이언스 at 2018-05-14T00:22:49-07:00. We are just promoting this video only for entertainment and educational purpose only. I hop you like our Video Search Engine. [xuv2tWGAQ8s]