38+34=____
25+75=____
98-89=____
77-49=____
I met many new words _______ I was reading the English novel.
结合如图所示所示实验,回答有关问题.
Amy was reading a book __________I came in.
圆柱底面直径为2cm,高为4cm,则圆柱的侧面积为( )cm2