高效液相色谱法系统适用性试验的内容包括
A. 理论板数
B. 分离度
C. 重复性
D. 拖尾因子
E. 灵敏度
What is the symbol of the Valentine’s Day?
A. Lovebird.
B. Cupid.
C. The shape of heart.
D. All of the above.
InAmerica, how many Valentine cards will be bought in a year?
A. Less than 900 million cards.
B. More than 900 million cards.
C. More than 600 million cards.
D. Not mentioned.
How do children inAmericacelebrate Valentine's Day?
A. Send flowers.
B. Send candy.
C. Send valentine cards.
D. All of the above.
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