Genetic inheritance question pls help

Manx cats do not have a tail. This abnormality is due to a dominant allele that leads to a spinal deformity. This allele, in the homozygous condition, is lethal. All Manx cats are heterozygous, genotype , at this gene locus. A cat breeder has a male Manx cat and female Manx cat, He allows them to breed and after several litters this pair of cats has produced cats and 12 cats with tails.
Cats use their tails to help them balance and also for communication to other cats. Side swishing indicates anger, a female's tail held to one side indicates to a male cat that she is sexually receptive, a fluffed up tail indicates fear or aggression, a raised curved tail indicates a friendly greeting and a lowered tail indicates submission.
(d) In some circumstances, such as during a war, many cats are abandoned by their owners and may become feral. How would you expect the frequencies of the and alleles, in a feral population originating from some abandoned pet Manx cats, to change over several generations of cats?