其中A， B， C三点为矩形截面中性层上的点，D， E， F  三点为矩形截面下边缘上的点
A、
B、
C、
D、

According to the conversation below, what does the woma...

单项选择题According to the conversation below, what does the woman think of Linda?   
M: Linda looked very tired these days. 
W：She looked OK to me (↗ ) A.
She saw Linda and me. B.
Linda said she was fine.  C.
She considered Linda was all right.

（True or False）The emissive power of a black body (per ...

单项选择题（True or False）The emissive power of a black body (per unit area per unit time) is directly proportional to the fourth power of its absolute temperature, True or False? （）
A、True
B、False

对接焊缝的收缩量比角焊缝的收缩量大正确错误

判断题对接焊缝的收缩量比角焊缝的收缩量大
正确
错误