煤垛的温度测量一般为三个月。
参考答案:对
When he knew the disappointing result of the exam, he seemed quite _______.
A.fed up
B.cast down
C.in vain
D.in amazement
人工幅度差系数一般为( )。
A.5%—10%
B.5%—15%
C.10%—15%
D.10%—20%