—Oh, my God! It's really heavy. I can't imagine how big it is! Is it an adult elephant?
A:grams
B:kilograms
C:kilometres
选出划线词语的用法与其他三项不同类的一项( )
已知函数f(x+1)是偶函数,当1<x1<x2时,f(x2)-f(x1)(x2-x1)>0恒成立,设a=f-12,b=f2,c=f3,则a,b,c的大小关系为 ( )