下列能溶于水的是（ ）
A. 大多数生物碱盐
B. 具有酚羟基的生物碱
C. 仲胺生物碱
D. 季铵型生物碱
凡是含氮的化合物均可视为生物碱。
A. 对
B. 错
What is the main idea of the news report?
A. More people buy education insurance.
B. The cost of raising a child in the UK has increased.
C. Many families cannot afford their children’s education.
D. Parents buy more expensive products for their children.
At which stage of the child’s growth do parents spend the largest amountof money?
A. When their child is between 2 and 5 years old.
B. When their child is between 5 and 10 years old.
C. When their child studies at university.
D. When their child starts a business.
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