凝汽式发电机组进行热能和机械能转换时采用的热力循环是（）。
A、正向卡诺循环；
B、逆向卡诺循环；
C、郎肯循环；
D、蒸汽燃汽联合循环。
参考答案：C
(2013·江苏苏、锡、常、镇一模)Time is of no importance to great thoughts, ________ are as fresh today as when they first passed through their authors' minds, ages ago.
A．what
B．that
C．which
D．where
临时宿舍的简易楼层高应控制在（）层以内。
A．1
B．2
C．3
D．4
