一个长方形的周长为30,若它的一边长x,则此长方形的面积为 [ ]
A.x(30﹣2x)
B.x(30﹣x)
C.x(15﹣x)
D.x(15+x)
答案:C
Miss Chen _____ just _____ to speak at the meeting... [ ]
A. has, been asked
B. has been, asked
C. have been, asked
D. have, been asked
施工成本计划中,()是以合同标书为依据。
A.指导性成本计划
B.对比性成本计划
C.竞争性成本计划
D.实施性成本计划