A:3,3﹣二甲基丁烷
B:3﹣甲基﹣2﹣乙基戊烷
C:1,1﹣二氯乙烯
D:2,3﹣二甲基戊烯
①从A、B两图可知,物体部分浸入水中受到的浮力大小是____ N.
②根据A、B、C的实验可知物体受到的浮力大小与____有关.
He ____(decide) to give up English. That makes us very surprised.