— She is a cook.
A：What is your mother doing?
B：What does your mother do?
C：What is your mother going to do?
D：How does your mother do?
濒临亚洲的大洋，按逆时针方向依次是（ ）
能够发生银镜反应且与丙酸互为同分异构体的是（ ）
已知集合M={x|x2+ax+b=0，x∈R}．
（Ⅰ）若集合M是单元素集，求实数a，b满足的关系式；
（Ⅱ）若1，3∈M，求实数a，b的值．
