则该植物一年生长在[30,40)内的频率是( )
A:0.80
B:0.65
C:0.40
D:0.25
计算图形中阴影部分的面积.(单位:厘米)
-- What do you think of Bill?
-- I used to think that he ____ (be) an honest boy.
下列词语中加横线字的注音,没有错误的一组是( )
Jumping out of ______ airplane at ten thousand feet is quite ______ exciting experience.