管道上安装节流装置时，如果孔板方向装反，会造成（）。
A.差压计倒指示
B.差压计指示变小
C.差压计指示变大
参考答案：B
I will thank Mary for her having offered to ________the baby while I went out.
A．have an eye for
B．keep an eye out for
C．keep an eye on
D．cast her eye over
处方保存三年备查的是
A．麻醉药品B．精神药品C．毒性药品D．放射性药品E．新药
