Mice of the yy genotype are gray, the Yy genotype is yellow, and the YY genotype perishes at the embryonic

Mice of the yy genotype are gray, the Yy genotype is yellow, and the YY genotype perishes at the embryonic stage of development. What will be the offspring from crosses: 1) (wives) yellow x (husband) gray; 2) (women) yellow x (husband) yellow? 3) In which cross can we expect a more numerous litter?

1) 1/2 gray, 1/2 yellow;
2) 2/3 yellow, 1/3 gray;
3) the offspring from the first crossing will be more numerous, since during the second crossing, part of the offspring dies at the embryonic stage of development.