单项选择题
A.0.85(1.2恒载标准值GK+1.4活载标准值QK) B.0.85(GK+Qk) C.0.75(GK+0.5QK) D.0.85(GK+0.5QK)
A.2 B.3 C.4 D.5
A.80%,且不宜小于70mm B.70%,且不宜小于70mm C.60%,且不宜小于70mm D.90%,且不宜小于70mm