物料管线一般都铺成（）坡度。
A、1/50
B、1/100
C、1/150
D、1/200
参考答案：C
A．一本物理课本厚度约为1dm
B．一个中学生的质量约为500g
C．家庭电路电压是380v
D．让人感觉舒适的温度是25℃
. -What is the book mainly about?
-Well, it ________ a little boy who suffered a lot during the war.
A．deals with
B．deals about
C．makes up
D．talk about
