多项选择题 水准测量成果校核的方法有（ ）。 A. 双面尺法 B. 附合测法 C. 往返测法 D. 闭合测法 E. 双仪器高法

单项选择题 Little Johnny felt the bag, curious to know what it ____.A.collectedB.containedC.loadedD.saved

单项选择题 What is a perpetuity? A、A perpetuity is a final annuity whose period is infinite. There is no future value for perpetuity. B、A perpetuity is an annuity whose period is infinite. There is no future value for perpetuity. C、A perpetuity is a final annuity whose period is infinite. There is no present value for perpetuity. D、A perpetuity is an annuity whose period is infinite. There is no present value for perpetuity.