Which action has a positive effect on air resources? O using fossil fuels
building new homes
O walking to work or school
O removing vegetation such as trees

walking to work or school

Explanation:

stops us from using cars which release gases that are is bad for the air quality

I think its C, walking to work or school

Explanation:

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.