简支板桥主要用于小跨度桥梁，跨径在( )m时，采用钢筋混凝土实心板桥。
A．2～4 B．3～6C．4～8 D．5～9
参考答案：C
. Little ______about his own health though he was very ill.
A．he cared
B．he cares
C．does he care
D．did he care
作业通道宽度应不小于（）m。
A.0.8
B.1
C.0.5
