Why do light-fur mice survive LESS often on dark rocks, compared to dark-fur mice?

for a creature with a lighter fur color it is next to impossible to blend into darker colored environments compared to darker fur colored creatures

Light-fur mice survive less often on dark rocks because they are easily seen by predators while dark-fur mice are harder to see.

The same situation applies to dark-fur mice on light rocks.

complete the square on the right side of the equation;

-5(x + 0)^2 + 15

answer: d. y = -x^2 + 15

the wires in the toaster turning red and the toast crisping and turning brown