If a horse has 40 chromosomes in its heart cells there will be blank chromosomes in its tail cells and blank chromosomes in its egg cells

40 in tail and 20 in egg cells.

Explanation:

If a horse has 40 chromosomes in its heart cells so there will be 40 number of chromosomes in its tail cells and 20 number of chromosomes in its egg cells because tail is also a part of body where mitosis type of cell division occurs means there is diploid number of chromosomes, while on the other hand, egg cells are the reproductive part where meiosis type of cell division occur in which haploid number of chromosomes are present.

they are known to reach a speed of 21 miles per hour

c is the answer : )               your welcome