If you cross a mule and a horse, you get a donkey. How many chromosomes does a donkey have?
horse=64 chromosomes
mule=63 chromosomes

62

Explanation:

31 pairs

A mule is the offspring of a male donkey (a jack) and a female horse (a mare). A horse has 64 chromosomes, and a donkey has 62. The mule ends up with 63. Mules can be either male or female, but, because of the odd number of chromosomes, they can't reproduce.

igneous rocks which formed by the crystallization of magma at the surface of the earth called extrusive rocks. they are characterized by fine-grained textures because the rapid cooling at or near the surface did not provide enough time for large crystals to grow.