Answer:
WwGg and wwgg
Step-by-step explanation:
Here you need to analyze what you want to breed and how you get it.
One of the parents was white so it has at least one of its alleles dominant (W), but the other one should be (w) because some breeding is colored.
And even though, we can't see its color we know it has at least one allele for green (G) because of the offspring, and the other one could be green (G) or yellow (g).
The other parent was yellow so, it's both alleles only can be (ww) and (gg) all recessive.
Now we can draw a Punnet square and discover that the F1 of those parents (WwGg and wwgg) is 50% white and 50% green.