一类高层民用建筑应按一级负荷要求供电，二类高层民用建筑应按二级负荷要求供电。
参考答案：对
This camera is of good quality. If it ______ break down within the first year, we would repair it at our expense.
A．would
B．should
C．could
D．might
一位母亲带了一个1岁的正常男孩进行体格检查，测得的头围应该是（）
A.38cm
B.40cm
C.46cm
D.48cm
E.50cm
