Among Delta-back stripped fish, there are two genes that segregate independently of one another. Suppose the alleles at the first locus are A (dominant) and a (recessive) and the alleles at the second locus are B (dominant) and b recessive). If an AABB fish mates with an aabb fish, and their offspring are inter-crossed, the proportion of F2 fish that show a recessive phenotype at the first locus and a dominant phenotype at the second is:

the answer is trees if i'm not mistaken

the relative atomic mass of an element is the mass of one atom of that element, relative to 1/12th of the mass of a  1212c atom. to convert to an absolute mass in kg, it is necessary to multiply by  1.661×10−271.661×10−27.

the relative atomic mass is roughly equal to the number of neutrons, plus the number of protons, in the nucleus of the atom.

for elements with more than one stable isotope (different types of nucleus with different numbers of neutrons but the same number of protons), the quoted mass is usually the average mass, weighted by the relative abundance of the different isotopes.