英语智力题
Ihavetwominutesinwhichtocatchatrain,andtwomilestogo.IfIgothefirstmileattherate(速率)of30milesper(每)hour,atwhatratemustIgothesecondmileinordertocatchthetrain?
A.30pm.hb.45mp.hc.60mp.hd.90mp.h
D的答案是对的吗,有没有不一样的了???