常用的硬度试验法为布氏硬度试验法、洛氏硬度试验法和维氏硬度试验法。
参考答案：对
— When would it be for you to go to the science museum with me?
— I am free this Friday afternoon. Let’s meet at 2 p.m. at the school gate.
A．convenient
B．pleasant
C．necessary
D．familiar
A．原子弹对聚变的链式反应不加控制，核电站控制裂变的链式反应速率
B．原子弹对聚变的链式反应不加控制，核电站控制聚变的链式反应速率
C．原子弹对裂变的链式反应不加控制，核电站控制裂变的链式反应速率
D．原子弹对裂变的链式反应不加控制，核电站控制聚变的链式反应速率
