问题
单项选择题
Tonnage openings must be closed by means of（）.
A.Press board
B.Steel hatch boards
C.Steel plates
D.Wooden hatch boards
答案
参考答案：C
搜题请搜索小程序“爱下问搜题”
Tonnage openings must be closed by means of（）.
A.Press board
B.Steel hatch boards
C.Steel plates
D.Wooden hatch boards
参考答案：C