The world's fastest passenger elevator (in the Shanghai Tower in China) travels at 18 m/s. The elevator ride from the 1st floor to the 128th top floor
takes 33 seconds. What is the distance between the 1st floor and the top?

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.

since electrons are negative the answer is neagtaive