On Monday morning a certain machine ran continuously at a uniform rate to fill a production order. At what time did it completely fill the order that morning?

(1) The machine began filling the order at 9:30 a.m.

(2) The machine had filled ~$1 \over 2$~ of the order by 10:30 a.m. and ~$5 \over 6$~ of the order by 11:10 a.m.

Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.

Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.

BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.

EACH statement ALONE is sufficient.

Statements (1) and (2) TOGETHER are NOT sufficient.

##### 考题讲解

（1）    只有开始时间，不能计算工作时长和结束时间，不满足要求。

（2）    根据条件2，从10:30到11:10的40分钟时间里，机器完成了(5/6-1/2)=1/3的工作量，所以每分钟完成1/3*1/40=1/120的工作量，到11:10已经完成了5/6的工作量，完成剩余的1/6工作需要20分钟(1/120*20=1/6)，因此可计算得到结束时间为11:30。题目得解。