AMC 10B/12B 2024 (Problem 14/9)

A dartboard is the region BB in the coordinate plane consisting of points (x,y)(x,y) such that x+y8|x|+|y|\le 8. A target TT is the region where (x2+y225)249(x^2+y^2-25)^2\le 49. A dart is thrown and lands at a random point in BB. The probability that the dart lands in TT can be expressed as mnπ\frac{m}{n}\cdot\pi, where mm and nn are relatively prime positive integers. What is m+nm+n?
(A)  39\text{(A)}\;39(B)  71\text{(B)}\;71(C)  73\text{(C)}\;73(D)  75\text{(D)}\;75(E)  135\text{(E)}\;135