I’m sorry, madam, those shoes are only ____ in small sizes. You can come again the day after tomorrow.

A．available

B．renewable

C．satisfying

D．acceptable

可作为提取方法的是

A．盐析法

B．结晶法

C．两相溶剂萃取法

D．铅盐沉淀法

E．水蒸气蒸馏法