30千克相当于60千克的( )%,80吨比50吨多( )%,40吨比70吨少( )%。(除不尽的,百分号前保留一位小数)
50;60;42.9
You can visit our homepage _______ the Internet, which, in reality, is popular _______ our fans.
A.from; to
B.via; with
C.into; amongst
D.with; into
混凝土结构梁的裂缝控制中,达到“构件虽有拉应力,但不超过混凝土的抗拉强度”是()级的要求。
A.一
B.二
C.三
D.四