梁中间支座上二排筋的长度怎样计算？
参考答案：取两侧较大净跨度的四分之一乘以2，加上中间支座宽度。
在0.02m2的物体表面上，受到压力是______时，物体表面受到的压强是200Pa．
The new invention may _____ changes in the way they do their work. [ ]
A. result from
B. expose to
C. lead to
D. put forward
