【单选题】以下溶剂可以用于青霉素萃取法分离纯化的有( )
【单选题】Little __ what others think.
【简答题】A.He is optimistic about the next year's market. B.He is worried about the increase in food prices. C.He is not sure about the petrol prices. D.He is pleasant for the decrease in unemployment.
【单选题】A. He is optimistic about it. B. He is curious about it. C. He is sure about it. D. He is pessimistic about it.
A.
He is optimistic about it.
B.
He is curious about it.
D.
He is pessimistic about it.
【单选题】★1126.早期连锁企业的连锁方式是( )。