下列家用电器中，利用电流的热效应的是[ ]
A.电风扇
B.电视机
C.电饭锅
D.收音机
答案：C
It was along the Mississippi River _____ Mark Twain spent much of his childhood. [ ]
A. how
B. which
C. that
D. where
履约担保可以实行分段滚动担保，一般为合同价的（）。
A、20%-25%
B、15%-20%
C、10%-15%
D、5%-10%
