预算定额是在（）基础上综合扩大编制而成。
A.概算定额
B.劳动定额
C.时间定额
D.施工定额
参考答案：D
方程x2-6x=0的根是______．
How often do you take a shower? I take a shower________/ wins/ a day.
A．won
B．once
C．win
D．one
