工字钢和槽钢的规格表示方法为( )。
A．直径(cm) B．高×腿宽×腰厚(mm)C．底×高(mm) D．边长(cm)
参考答案：B
This is the best hour I can I in the past twelve years. [ ]
A. know; have had
B. remember; had
C. think of; have had
D. think out; had
石油凝固点≥40℃，被称为（）。
A.高凝油
B.常规油
C.低凝油
D.特稠油
