Give two reasons why plant hormones may be released

During times of stress such as dryness and lack of water(ABA is released which causes the stomata to close)

During seed germination(mainly gibberellins)

During phototropism and geotropism(auxins)

Hope this helps:))

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.