A:2
B:23
C:4
D:6
若一个椭圆长轴的长度、短轴的长度和焦距成等差数列,则椭圆的离心率是( )
Miss Read is good ____________ music. She is good ____________ children in the music club.
x(元/件)
38
36
34
32
30
28
26
t(件)
4
8
12
16
20
24
假定试销中每天的销售量t(件)与销售价x(元/件)之间满足一次函数.