计算:a2•a3÷a4的结果是______.
a2•a3÷a4=a2+3-4=a,
故答案为:a.
To show our respect, we usually have to take our gloves off _____we are to shake hands with. [ ]
A. whichever
B. whenever
C. whoever
D. wherever
105-J LPS-88动作报警而LPSI-88未报警,如何处理。