.It was from only a few supplies that she had bought in the village______the hostess cooked  such a nice dinner.

A．where

B．that

C．when

D．which

在一容积不变的封闭容器内理想气体分子的平均速率若提高为原来的2倍，则( )。

A．温度和压强都提高为原来的2倍
B．温度为原来的2倍，压强为原来的4倍
C．温度为原来的4倍，压强为原来的2倍
D．温度和压强都为原来的4倍