题干
Boys and girls, please treat this exam with _______ usual mind. Calm down, and you had better________ your best to get good grades.
A：the, trying
B：a, try
C：an, to try
答案(点此获取答案解析）
B
，
，
，
，则数列
的通项公式
为
⑥蒸馏时，将温度计的水银球靠近蒸馏烧瓶支管口。
