In examining M. rattus, you realize that the animal has many eyecolors. You perform the following crosses.
Cross         Parents                                            Progeny (ratio of phenotypes)
1                blue eye X yelloweye                     all green
2                blue eye X blueeye                         3 blue : 1 red
3                blue eye X browneye                     1 blue : 1 green : 1 yellow: 1 red
4                yellow eye X redeye                       2 red : 1 yellow: 1 brown

a) What is the pattern of dominance for eye color? Show yourwork.
b) What phenotypic ratio would you see if you mated the blue eyeanimal in cross 3 with the red eye animal in cross 4?