Aspectrum for a given element is unique for that element. why is that so?
a. no element has more than 2 electrons in the first shell.
b. each element has an unique arrangment of electrons
c. atoms of different elements have different masses
d. atom nuclei contains no electrons

What is one way intensive agriculture can contribute to climate change? a. tree loss to agriculture increases earth's albedo b. livestock manure absorbs greenhouse gases c. large herds of livestock release greenhouse gases d. fewer trees are available to replenish petroleum stores appex