1)
T- tall allele;
t- small allele;
B-brown allele
b- white allele
The male has recessive traits for bothe the height gene and the color.
He is small and white and to express these traits it means his genotype is: ttbb.
He has both alleles, of each gene, recessive to express his caracteristics.
2) The female genotype is unknown but we know she is tall and brown.
There are 2 possibilities for her genotype:
TTBB or TtBb
In the first case, she would be dominant homozygotic -both alleles, of each gene, are dominant.
The second case, she would carry a recessive allele and a dominant allele. This makes her heterozigotic for both genes.
3)Due to the two possibilies of the female genotype, there will be two different results for the probability of the offspring.
First : ttbb x TTBB- the probability of having small and white offspring would be
0%. That's because the offspring would be: TtBb- expresses the tall and brown traits.
Second: ttbb x TtBb- the probability of having small and white offspring would be
25%. That's because 1/4 of the offspring could have the genotype ttbb
.For better understanding i made the punnet square (see the blue part).