饱和溶液____是浓溶液,如熟石灰的饱和溶液;不饱和溶液____ 是稀溶液,如接近饱和的硝酸钾溶液.(填“一定”、“不一定”)
A. Take turns.
B. Keep your desk clean.
C. Work quietly.
D. Talk quietly.
E. Keep to the right.
1950年,中央人民政府颁布的土地改革法令是( )
用反证法证明“若a>b>0,则a2>b2”时,应假设( )