在机械加工工艺过程中，安排热处理工序的目的是改变材料的力学性能和消除内应力。( )
参考答案：对
(2013·辽宁大连双基测试)________ a man's age, he can reduce it several years by wearing a confident smile.
A．Whichever
B．Whatever
C．Whenever
D．However
发电机励磁回路发生一点接地时，应投入励磁回路两点接地保护.
