单项选择题
A.1.00 B.0.50 C.0.25 D.0.45
A.(x-y)(z-y)(z-x) B.(y-x)(y-z)(z-x) C.(x-y)(y-z)(x-z) D.(x-y)(y-z)(z-x)
A.5a/6 B.6a/5 C.6a/7 D.7a/6