Which of these reactions is an addition reaction?
h4c2+ br2 → h5c2br + hbr
oh4c2+ hbr → h5c2br
h5c2ci+ naoh → h5c20h + naci

there is none because earth is stationary and flat.

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

if it's not useful, feel free to report for mistake in answer.

the objects have the same charge.