— I haven't finished my essay because the computer broke down when I was downloading the

required data last night.

— Really! You could have turned to me. I         mine. [      ]

A. didn't use

B. won't use

C. hadn't used

D. wasn't using

设计带有活动镶件的注射模时应注意：活动镶件在模具中应有可靠的定位，它和安放孔的配合面一般应设计成（）的斜面。

A、3º～5º

B、4º～6º

C、5º～8º