Answer:
a)
Homozygous for orange will be RR
Homozygous for cream will be rr
On crossing the two cucumbers, the genotype for all the off springs in the F1 generation will be Rr
Therefore all the off springs in the F1 generation will be phenotypically Orange since R is dominant over r
When the F1 are crossed. The genotype for the off springs will b; RR, Rr, Rr and rr. Therefore 3 orange and 1 cream
b)Back cross with orange(RR×Rr)
Genotype: RR, RR,Rr, Rr
Phenotype;All orange
c)Back cross with cream(Rr×rr)
Genotype: Rr, Rr, rr, rr
Phenotype: 2 orange and 2 cream