boxes of fruit and vegetables have been delivered to h around britain for a few years
问题描述：
boxes of fruit and vegetables have been delivered to h around britain for a few years
请问h填什么?
太阳质量为1.98乘以10的33次方,地球质量为5.98乘以10的三次方亿吨,问太阳质量是地球的几倍?（1吨为10的六次方克）
已知（m+n）的二次方=10,（m-n）的二次方=2,求m的四次方+n的四次方的值.
答
1、homes
3、m^4+n^4=（m^2+n^2）^2-2(mn)^2=（（m+n）^2-2mn）^2-2(mn)^2=25-2=23
(m+n)^2=7 (m-n)^2=3 从而mn=1 两式相减