Please help! What is the difference between carbon-13 and carbon-14?

the number of electrons
the number of neutrons
the number of nuclei
the number of protons

What came first egg or chicken? and is tomato a vegetable or a fruit?

All ova contain sex chromosomes corresponding to: x y xx xy

Which is a function of vascular tissue? a. to perform photosynthesis b. to transport water and nutrients c. to absorb minerals and sugar d. to interact with soil fungi