A:若
B:若
C:若
D:若
It took the man less time to fly to Xi'an than it _______ there.
某化学兴趣小组为测定Fe、Cu、Ag三种金属的活动性顺序,选用下列各组试剂,你认为不可行的是( )
如果m和n互为相反数,则化简(3m﹣2n)﹣(2m﹣3n)的结果是( )