Methane gas must be removed from landfills because

it is highly explosive is the correct answer.

Explanation:

Methane gas must be removed from landfills because it is highly explosive.

Methane gas is highly explosive because it carries chemicals that are present at an explosive level.

Methane gas concentration in landfills is about 50 percent higher than its Upper Explosive Limit and it is expected to cause an explosion hazard.

landfill gas(methane gas) is produced due to decomposing the waste in landfills and landfills gas is dangerous as it results in the greenhouse effect.

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.

the answer would be..

b. sucking