A:物体2s末的速度为20m/
B:物体2s末的速度为10m/
C:物体2s内下落的高度是40m
D:物体2s内下落的高度是10m
根据句意及首字母提示完成单词We went to a summer c____ last year.There w____ many trees on the mountains five years ago(以前).We are studying hard for e____ .—He was an English teacher.—R____ ? Did he teach you?What an a____ classroom! It’s too dirty!
c水=4.2×103J/(kg•℃),则:
型 号
BJ﹣2008
水 容 量/L
80
自身质量/kg
40
集热管面积/m2
3
效 率
70%
直线(2+λ)x+(λ﹣1)y﹣2λ﹣1=0经过的定点坐标为____ .