电力系统发生短路故障时，继电保护必须迅速切除故障，保证（）部分继续运行。
A.其他
B.无故障
C.正常
D.全部系统
参考答案：B
Evelyn Mastakis, CFA, is a quantitative analyst in a local securities firm and does research about the difference between ordinary annuity and annuitydue. If both have the same number of payments, payment amount, and frequency of payments and are discounted at the same positive rate, the present value of the ordinary annuity is:（）
A. greater than the present value of the annuity due.
B. less than the present value of the annuity due.
C. equal to the present value of the annuity due.
当事人申办有强制执行效力的债权文书公证的手续是怎样的？
