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).
Evidence would the fossils they left in the grounds they found.
The combined mass of rock 1 and 2 = 19.28 + 25.3
= 44.58
Difference between rock 3 and combined rocks
= 46.3 - 44.58
= 1.72 grams
therefore, the third rock was 1.72 grams greater than the combined mass of the other two rocks.
The correct answer for the given question above would be option B. Thale cress <span>is a plant that is genetically engineered with genes that break down toxic materials, so this would be a transgenic type of organism. By definition, transgenic organisms undergone genetic engineering wherein genes of a particular specie is modified or transplanted into another. Hope this helps.</span>