A.5:6
B.6:5
C.2:15
D.15:2
答案:A
a、b两物体从同一位置沿同一直线运动,它们的速度图象如图所示,下列说法正确的是
A.a、b加速时,物体a的加速度大于物体b的加速度
B.20秒时,a、b两物体相距最远
C.60秒时,物体a在物体b的前方
D.40秒时,a、b两物体速度相等,相距200m
— Jim has his wife do all the housework!Isn't he wise?
— Not really.He is________.[ ]
A. more wiser and lazy
B. wiser than lazy
C. more lazy than wise
D. lazier than wise