If the mutation takes place in a gamete that ends up forming an embryo, the mutation will be passed on to an offspring. This can also occur if the mutation occurs early in an embryos development, and the cell becomes one of the gamete forming cells, the mutation will be passed on to their offspring.
The gene is responsible for the cat's hearing.
If the strand of Nucleic acid does not have a U - it must be DNA. Any sequence with a U is considered to be RNA. Therefore, CAGACT is considered to be a strand of DNA.