梯形上底与下底的和是8厘米，高是5厘米，它的面积是______厘米2．
8×5÷2，
=20（平方厘米）．
答：它的面积是20平方厘米．
故答案为：20．
5. He will never _______ though every means ________ tried already.
A．lose heart; has been
B．lose heart; have been
C．lose his heart; was
D．lose his heart; had
汇票按照信用性质的不同，可分为商业汇票和（）。
A.银行承兑汇票
B.跟单汇票
C.银行汇票
D.提示汇票
