﹣32×2﹣3 ×(﹣2)2.
解:原式=﹣9×2﹣3×4
=﹣18﹣12
=﹣30.
在水平面上,一辆小车从静止开始以的加速度前进。有一人在车后与车相距处,同时以的速度匀速追车。
小题1:试分析人能否追上车?
小题2:若能追上,求追上时小车的速度;若追不上,求人与车的最小距离。
I had just got up and was about to cook my breakfast ___the telephone rang loudly, but it hung up __I could answer it .
A.when ; before
B.when ; as
C.as ; after
D.while ; when