A:5km/h
B:50km/h
C:100km/h
D:150km/h
一辆质量为5t的汽车,通过拱桥的最高点时对拱挢的压力为4.5×104N,桥的半径为16m,则汽车通过最高点时的速度为 (g取10m/s2)( )
____the doctors in their hospital is about one thousand, and sixty percent of them___________ women.