金属洛氏硬度试验时,从初试验力施加至总试验力的时间()。
A.不小于3s且不大于8s
B.不小于1s且不大于8s
C.不小于1s且不大于3s
D.不小于1s且不大于5s
参考答案:B
— This is an exciting holiday. People usually make pumpkin lanterns and go to parties. Children wear (穿戴)
masks and dress up in costumes, What holiday is it?
— It's _____________. [ ]
A. Halloween
B. Easter
C. Christmas
正槽溢洪道是由()、()、()、()、()五部分组成,其作用是饶过挡水建筑物将库水平顺引入挡水建筑物下游的原河道。