A:On hearing, got
B:At heard, changed
C:On hearing, went
D:On heard, appeared
答:两位数与三位数相乘,积最大是____位数.积最小是____位数.
已知sinα=13+cosα,且α∈(0,π2),则cos2αsinα+π4的值为____
一天中气温最高和最低值分别出现在( )