题干
— ________ Maria from Japan? — Yes, ________.
A：Are; they are
B：Is; she is
C：Does; she does
答案(点此获取答案解析）
B
— ________ Maria from Japan? — Yes, ________.
A：Are; they are
B：Is; she is
C：Does; she does
,a,b,c∈R,且a+b>0,a+c>0,b+c>0,则f(a)+f(b)+f(c)的值( )