从（）开始西欧皇帝必须要经过教皇的加冕。
A、凯撒大帝
B、奥托一世
C、查理曼大帝
D、查理一世
参考答案：C
甲水泥厂因无力支付建厂赊乙钢材厂钢材的货款，遂向乙钢材厂提供了一批水泥用来抵账。后乙钢材厂将该批水泥出售给丙施工单位，则关于该水泥买卖合同的效力，下列说法正确的是( )。
A．水泥买卖合同为有效合同
B．水泥买卖合同因乙钢材厂超越经营范围而无效
C．水泥买卖合同因乙钢材厂超越经营范围而效力待定
D．水泥买卖合同因乙钢材厂超越经营范围而可撤销
An annuity will pay eight annual payments of $ 100, with the first payment to be received one year from now. If the interest rate is 12 percent per year, what is the present value of this annuity（）
A. $ 556.38.
B. $1377.57.
C. $ 496.76.
