装在吸水管末端的滤水器的作用是用来控制排水量的大小的。
参考答案：错
体外电除颤时，选择能量水平，首次常为（）
A.50J
B.100J
C.200J
D.300J
E.360J
The researchers found clear and convincing evidence ________ happiness is the key when it comes to better health and longer lives.
A．where
B．whether
C．how
D．that
