用长为1、4、4、5的线段为边作梯形，则这个梯形的面积为______．

短文改错题。One Sunday last month I go shopping with my friends. Luckily in a crowded store, I had my wallet losing. I was such upset that I almost shouted. I was afraid to tell to my parents the truth. So I went back to school without some money. I didn’t know what to do next. I didn’t eat anything Monday. My roommate Mary found something wrong with me but she asked me about the problem. I told him the truth. Then Mary lent me some money, with that I lived through the terrible week.

注入印度洋的河流是（　　）

A．湄公河

B．长江

C．恒河

D．勒拿河

代谢性碱中毒的特征是（）。

A.HCO₃^-下降，pH下降，PaCO₂正常

B.HCO₃^-上升，pH上升，PaCO₂正常

C.HCO₃^-下降，pH上升，PaCO₂下降

D.HCO₃^-正常，pH下降，PaCO₂下降

E.HCO₃^-正常，pH下降，PaCO₂上升

胶带输送机必须装设（）。

A.驱动滚筒防滑保护

B.不需任何保护

C.堆煤保护

D.防跑偏装置

小腹泻轻型与重型的主要区别点是（）。

A.每日大便次数

B.有无呕吐

C.有无发热

D.脱水、电解质紊乱

E.大便性质