火花塞一般更换周期为——
A. 1000km
B. 2000km
C. 3000km
D. 20000km
What is the dialogue mostly about?
A. taking out a loan
B renegotiating terms
C. financing a new business
D. making an early payment
What will the man likely do?
A. change his business plans
B. try to get a loan elsewhere
C. pay off some of his business's debts
D. ask for another accountant's opinion
制备生物医用材料时，建议从下列物质中选用（）为交联剂交联胶原
A. 京尼平
B. 戊二醛
C. 乙醛
D. 甲醛
E. 醋酸
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