At 9 a.m, a hiker was due south of point P

问题单项选择题

At 9 a.m, a hiker was due south of point P. What direction was point P from her position at noon ？（）
(1)From 9 a.m until 11 a.m she walked due east at 2 miles per hour, and from 11 a. m until noon, she walked due north at 3 miles per hour.
(2)At noon, she is exactly 4.5 miles from point P.

A．条件(1)充分，但条件(2)不充分．

B．条件(2)充分，但条件(1)不充分．

C．条件(1)和(2)单独都不充分，但条件(1)和条件(2)联合起来充分．

D．条件(1)充分，条件(2)也充分．

E．条件(1)和条件(2)单独都不充分，条件(1)和条件(2)联合起来也不充分．

答案

参考答案：E

解析：

at noon指正午12点根据(1)可知此徒步旅行者向东走了4英里后又向北走了3英里，但因为不知道上午9点时其与P点的距离，所以无法得到正午时她在P点的哪个方向；由(2)正午时她距P点4.5英里更无法得到其距P点的方向；(1)+(2)同样无法确定P点在该徒步旅行者的哪个方向。