A:N2
B:NH3
C:H2O2
D:CH4
— Your car should be ready next Tuesday.
— We were ____ hoping you'd be able to do it by this Friday.
A,B两站相距s,将其分成n段,汽车无初速由A站出发,分n段向B站作匀加速直线运动,第一段的加速度为a.当汽车到达每一等份的末端时,其加速度增加 an ,求汽车到达B站时的速度.