A study reveals that more than half of Americans lose their TV remote between one and five

times a week,____11 percent misplace it six to ten times. [ ]

A.when

B.as

C.while

D.but

高参数、大容量锅炉的水循环安全检查时主要是检查（）。

A、汽水分层

B、水循环倒流

C、下降管含汽

D、膜态沸腾