住宅按照层数，分为低层住宅、多层住宅、中高层住宅和高层住宅，其中中高层住宅为（）层。
A.4～6
B.7～9
C.7～10
D.10层及以上
参考答案：B
行之有效的安全度夏措施有哪些？
To meet a government requirement, a bottler must test 5 percent of its spring water and 10 percent of its sparkling water for purity. If a customer ordered 120 cases of spring water and 80 cases of sparkling water, what percent of all the cases must the bottler test before he can send it out
A．6.5%
B．7.0%
C．7.5%
D．8.0%
E．(E) 8.5%
