A.2
B.4/3
C.π
D.3
[单选题]( ).A.2B.4/3C.πD.3
[单选题]A.3636m/sB.3810m/sC.4000m/sD.3000m/s
[判断题]A.对B.错
[单选题]A.28650B.27000C.28800D.28500
[单选题]A.1B.2C.3D.4
[单选题]A.0.30B.0.15C.0.60D.0.90
[单选题]A.49.5,98B.98,49.5C.99,98D.98,99