What are the functions of the smooth and rough e. r.s

The endomembrane system is a group of cell membranes and organelles that are mutually interconnected, either by being directly continuous with one another or by sending one another vesicles—little spheres of membrane then can bud off from one membrane and fuse with another. 

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Explanation:

air, water, heat and noise pollution can all be caused by producing and using technology. consuming resources - non-renewable resources, including precious metals like gold, are used to make technology

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.