洛氏硬度按选用的总试验力及压头类型不同,常用的标尺有()、()和()三种,它们的总试验力分别为588.4N、980.7N和1471.0N。
参考答案:HRA,HRB,HRC
一种树苗的成活率是96%,为了保证成活200棵,至少要种______棵树苗.
—How was your job interview?
—Oh,I couldn’t feel _______.I hardly found ______ answers to most of the questions
they asked.
A.better,exact
B.easier,adequate
C.worse,proper
D.happier,urgent