一物体作匀加速直线运动,通过一段位移Δx所用的时间为t1,紧接着通过下一段位移Δx所用时间为t2。则物体运动的加速度为()
A.
B.
C.
D.
参考答案:A
目前世界上石油储量最大、生产和输出石油最多的地区是
A.西欧
B.东南亚
C.中东
D.非洲北部
You are late. If you ____ a few minutes earlier, you ____ him.
A.came; would meet
B.had come; would have met
C.come; will meet
D.had come; would met