How is the dna in a prokaryote different from the dna in a eukaryote?
a. eukaryotes do not have alleles.
b. only prokaryotes are diploid.
c. prokaryotes do not have genes.
d. dna is in a nucleus in eukaryotes.

The correct answer is D) DNA is in a nucleus in eukaryotes.

Prokaryotes are those organisms that lack a well defined nucleus and membrane bound subcellular organelles (like endoplasmic reticulum, golgi complex, mitochondria). The genetic material lies in the cytoplasm of the cell in these organisms.

Example - Bacteria like E.coli.

On the other hand, eukaryotes are those organisms that contain a well defined nucleus that possesses the genetic material (DNA). These organisms also contain membrane bound subcellular organelles.

Example - Plants and animals.

the answer to you question is   jet streams

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.