How many cycles of pcr would it take to create 16 copies of a dna molecule?

Explanation:

The number of double stranded DNA pieces is doubled in each cycle, so that after n cycles you have 2^n (2 to the n:th power) copies of DNA. For example, after 10 cycles you have 1024 copies, after 20 cycles you have about one million copies, etc.

a community that experiences major changes undergoes progress

b is dominant over the allele for the white fur.