题目

All the students are enjoying this school trip.  A.very            B.a lot        C.a lot of     D.lots of 答案：B16．已知实数m、n满足m=$\frac{\sqrt{{n}^{2}-4}+\sqrt{4-{n}^{2}}+4}{n-2}$，求|m-2n|+$\sqrt{8mn}$的值．