设A={x|x²+8x=0}，B={x|x²+2（a+2）x+a²-4=0}，其中a∈R，如果A∩B=B，求实数a的取值范围。

Water can absorb and give off a lot of heat without big changes in temperature,thus creating a___environment.

A．peaceful

B．sensitive

C．common

D．stable