Surface area o fthe ball = 4 * 3.14 * radius^2
if diameter = 1.680 then radius = 1/2 * 1.680 = 0.84
so surface area = 4 * 3.14 * 0.84^2 = 8.862
Red die: 1,2,3,4
green die: 4,3,2,1
I'm not sure if that's the answer you were looking for, but hopefully that helps.
