Ihave some question on alef website

Give the set of reactants (including an alkyl halide and a nucleophile) that could be used to synthesize the following ether: draw the molecules on the canvas by choosing buttons from the tools (for bonds and charges), atoms, and templates toolbars, including charges where needed. ch3ch2och2ch2chch3 | ch3

If i had 2 m naoh solution, what does the 2 m stand for? 2 molar, but 2 of a solute in 1

Why do electrons further from the nucleus have more energy