1设a>b>c>0,则2a^2+1/ab+1/a(a-b)-10ac+25c^2的最小值
A2 B2 C2×根号5 D5
2设实数想x,y满足3≤xy^2≤8,4≤x^2/y≤9,则x^3/y^4的最大值是?