Which letter replaces the question mark ?

Question

Answer 1

z is at 26
s = 19 & g = 7 total is 26
same way for m = 13, d= 4 & i = 9 total is 26
F=6 E=5 H=8 & g=7 total is 26

Answer 2

F(6)+e(5)+H(8)+G(7)=26