在等差数列{a_n}中，若a₂=4，a₄=2，则a₆=（　　）

寒冷的冬天，气温在0℃以下，公园里的冰雕会慢慢减小，这是因为（   ）

A. How much are they?

B. Can I help you?   

C. OK. We'll take them

D. What size ?

E. Yes. But I like the blue pair.

A:____

B: Yes. A pair of shoes for my son.

A:____

B: Size6.

A: How about this pair?

B: Are they nice，John?

C:____

B: Are the blue ones all right?

C: Yes. they are.

B:____

A: They are 40 yuan.

B:____