Answer:
The total additive genetic effect = 0.64
Explanation:
For C1c1C2C2, we are assuming that additive effect of C2C2 will result in a co-dominant trait that is totally different from the original one at both of the color1 and color2 loci.
The total additive genetic effect = C1c1C2C2 = (+0.15) + (-0.01) + (+0.25) + (+0.25) = 0.64