Not until the taxi disappeared in the distance     her handbag was gone.

A．Tina had found

B．had Tina found

C．did Tina find

D．Tina found

抽样调查某地区高血压患病情况，欲估计该地区高血压总体患病率，其总体率的表示符号一般用（）。

A．

B．μ

C．p

D．π

E．s