决定基金期限长短的因素主要有（）。
A．发行规模
B．宏观经济形势
C．基金本身投资期限的长短
D．基金份额交易方式
参考答案：B, C
Nearby _____ in which they had spent their summer vacation. [ ]
A. was two houses
B. two houses were
C. were two houses
D. are two houses
A是一种常见的单质，B、C为常见的化合物，A、B、C均含有元素x，它们有如图所示的转化关系(部分产物及反应条件已略去)。下列说法中正确的是
A．X元素可能为铝
B．反应①和②互为可逆反应
C．X元素可能是金属，也可能是非金属
D．反应①和②一定为氧化还原反应
