The weather here is different from ________ in Beijing, but the people here are as friendly as _________ in Beijing.
A：those; that
B：the one; those
C：the one; that
D：that; those
When I entered the room, I found he was b____ in his work, so he didn't notice me come in.
在圆的周长C=2πR中，常量与变量分别是（ ）
