装置开车,加热炉引燃料油循环时应()。
A、打开油嘴上游阀
B、打开燃料油线放空阀
C、关闭所有油嘴阀
D、投用温控阀
参考答案:C
Look and write.
1. The bag is _______ the desk.
2. The pencil-box is _______ the bag
3. The pen is _______ the pencil - box.
4. The dog is _______ the chair.
5. A: What's this, pl _______ se?
6. B: It's a b _______ k.
关于法洛四联症矫治术,下述哪项不恰当()
A.疏通右室流出道
B.修补室间隔缺损
C.必须有足够的右心室末容量
D.必需两侧肺动脉发育良好
E.一般在中度低温(25~26℃)体外循环下施行