I'll ______ advertisements after school so that we can tell people about the park clean-up. [ ]

A. hand out

B. hand in

C. put off

D. put on

煤层中夹矸的单层厚度（）所规定的煤层最低可采厚度时，被夹矸所分开的煤分层应作为独立煤层，一般应分别计算储量。