不会吧,我这里有一道prep的题: If it took Carlos ½ hour to cycle from his house to the library yesterday, was the distance that he cycled greater than 6 miles? (Note: 1 mile = 5,280 feet) (1) The average speed at which Carlos cycled from his house to the library yesterday was greater than 16 feet per second. (2) The average speed at which Carlos cycled from his house to the library yesterday was less than 18 feet per second. 是一般疑问句,两个选项都是说明不会大于6mile, 正确答案是E而不是D!!! -- by 会员 zjzw1988 (2012/7/18 7:47:16)
不是的 I、v>16feet/s=10.9mile/h vt=d d>10.9*1/2=5.45 II、v<18feet/s=12.27mile/s d<6.135 你算错了 |