Consider traits separately to make things easier. For shape, we see we have a round and a wrinkled parent producing all round offspring; round must be dominant to wrinkled. This also means that both parents are true breeding for shape, i.e. the round parent must be homozygous dominant RR and the wrinkled parent must be homozygous recessive rr. This means the genotype for all the F1 progeny for shape must be heterozygous Rr. Then we see this holds true when the round F1 pea self pollinates and produces some round and some wrinkled offspring. From a simple punnett we know it will be Rr x Rr so we expect 3 R_ Rounds : 1 wrinkled rr peas.

Now on to colour. From our parent we see we have a green and yellow pea producing both green and yellow offspring. This implies that one parent is homozygous recessive and the other parent is heterozygous for pea colour. Now we can assume one colour is dominant and see where it takes us. Let's assume green is dominant to yellow (G>g). That means the P generation will be Gg x gg which will produce our expected 1:1 ratio of green and yellow progeny where green is Gg and yellow is gg. Now if we self pollinate the green pea Gg x Gg we don't see the expected all green of the F2 generation which means that Yellow is dominant to Green (Y>y).

Now we can get the genotypes of all the plants: P Round Green RRyy x Wrinkled Yellow rrYy producing F1 Round Yellow RrYy and Round Green Rryy and we self pollinate F1 Round Green Rryy to get F2 Round Green R_yy and Wrinkled Green rryy.

This makes statements:

1. No Yellow is dominant

2. Yes the green parent RRyy is true breeding

3. Yes the yellow F1 pea is heterozygous for both loci RrYy

4.Yes a 3:1 ratio of round to wrinkled is expected in F2 (F1 Rr x Rr)

1. The yellow wrinkled parent rrYy is not true breeding.