区间±1.96可用来（）。

A．估计95%的医学参考值范围

B．估计样本均数的95%置信区间

C．表示95%的总体均数在此范围内

D．估计总体均数的95%置信区间

E．表示样本变量值的分布情况

Green economy offers a new model ______ people could both protect the climate and develop the economy, according to what Li said at the International Cooperative Conference on Green Economy and Climate Change.

A．how

B．why

C．where

D．which