项目可行性研究的核心内容是（）。
A．投资估算与资金筹措
B．需求预测和拟建规模
C．建设条件与厂址方案
D．项目经济评价
参考答案：D
苹果的个数含有因数5，又是17的倍数．苹果至少有多少个？
— My sister is very upset today.
— It's your fault. You ______ the bad news to her yesterday. [ ]
A. should tell
B. should have told
C. shouldn't have told
D. must tell
