正常肝脏血流量每分钟约（）
A.500ml
B.800ml
C.1200ml
D.1500ml
参考答案：D
—_____ are they doing?
—They are running. [ ]
A. Who
B. Whose
C. What
D. Where
发包人在施工中若要对工程设计进行变更，应提前( )天书面通知施工承包人。
A．6
B．10
C．14
D．30
