We're do volcanoes usually form please help me A within 10 miles of the ocean B between earths mantle and core C at fault lines between tectonic plates D within the boundaries of the U. S.

genetic variation can be caused by mutation (which can create entirely new alleles in a population), random mating, random fertilization, and recombination between homologous chromosomes during meiosis (which reshuffles alleles within an organism's offspring).

b. climate change will cause an increase in biodiversity of all ecosystems.

hope this