Answer:
1. Probability is 1/2
2. Parents phenotypes:
TTHh = white spots, short hair
Tthh = white spots, long hair
Explanation:
This question involves two different genes coding for spot color and hair length in cats respectively. In the first gene, the allele for white spots (T) are dominant over the allele for solid color (t) while the allele for short hair (H) is dominant to long hair (h).
According to this question, a cross between parent cats was performed as follows: TTHh x Tthh. The following gametes will be produced by each parent:
TTHh - TH, Th, TH, Th
Tthh - Th, Th, th, th
Using these gametes in a punnet square (see attached image), 16 possible offsprings will be produced. However, according to the question, 1/2 of the offsprings will probably be white-spotted and long-haired. The phenotypes of the parents are as follows:
TTHh = white spots, short hair
Tthh = white spots, long hair