图示为中枢神经系统和膝跳反射模式图，请据图回答：
物质的用途主要由其化学性质决定的是（ ）
下列词语中，划线的字读音正确的一项是（ ）
Sam: Come on, it's time for school.
Mike: What class do you have today?
Sam: I have math, music and PE. How about you?
Mike: I have English, art and music.
Sam: I like English. What about you?
Mike: I like music.
选择正确的答案填在括号里。
化学就在我们身边，通过一年的学习，我有了许多收获：
