当有可靠防浪墙时,心墙顶部高程应高于(),且不低于()。
参考答案:高出设计洪水位0.3-0.6m;校核水位
The fire started on the second floor and it wasn't long ______ the whole building was burned down.
A.while
B.when
C.after
D.before
我国农村养老保险费()
A.只能预交五年
B.可以预交也可以补交
C.可以预交但不可以补交
D.可以补交五年以内的