Final answer:
The liver cells of a cat will have 40 chromosomes, as they are diploid cells, containing two sets of chromosomes, one from each parent.
Step-by-step explanation:
If the egg cells in a cat have 20 chromosomes, then the liver cells of a cat, which are diploid cells, would have 40 chromosomes. This is because somatic cells such as liver cells contain two sets of chromosomes, one from each parent, making them diploid. The gametes, or sex cells like sperm and egg, which are haploid, contain only one set of chromosomes. This distinction is pivotal to sexual reproduction, where the fusion of two haploid gametes creates a diploid zygote with the full chromosome complement of the species.