问题
单项选择题
Consider a 10 percent, 10 - year bond sold to yield 8 percent. One year passes and interest rates remained unchanged (8 percent). What will have happened to the bond's price during this period（）
A. It will have decreased.
B. It will have increased.
C. It will have remained constant.
答案
参考答案：A
解析：
The bond is sold at a premium, as time passes the bond's price will move toward par. Thus it will fall. N=10; FV=1000, PMT=100; I=8; CPT PV=1134. N=9; FV=1000, PMT=100; I=8; compute PV=1125.
Cu2S+3SO2+2FeO(炉渣)
2Cu2O+2SO2；2Cu2O+Cu2S
6Cu+SO2↑。
6Cu+SO2↑中，作氧化剂的只有Cu2O