腐植酸钠用量根据锅炉给水的总用度确定，每1mol/L硬度，加药剂为每吨水（）克。
A.1至2
B.3至5
C.5至10
D.10至15
参考答案：B
．— Excuse me, could you tell me where I could make a call?
— Sorry, I’m a stranger here.
— ____.
A．Thanks a lot
B．That’s a pity
C．Thanks anyway
D．I’m sorry to hear that
薤白的主治病证是（）
A．寒湿痹痛
B．胸痹心痛
C．热毒血痢
D．寒饮咳喘
E．寒疝腹痛
