给水温度下降，锅炉燃料量不变的情况下，过热汽温（）。
A、下降
B、升高
C、不变
参考答案：B
有效磁导率
The _______ contract is a contract between a party who agrees to accept the risk and a party seeking protection from the risk
A．payment B．productionC．shipment D．insurance
