Answer:
B is the best answer for this question
Distance is a scalar and measured only by units (meters, feet). Position is a vector and depends on where the origin is. It can be negative or positive and has direction.
I don’t know, which statement ahh I see white screen lol
Unit is m^3 or metres cubed. You need to multiply the three dimensions of the block to get the volume.
A ruler can be used to measure the edges.
(a) We can find the current flowing between the walls by using Ohm's law:

where

is the potential difference and

is the resistance. Substituting these values, we get

(b) The total charge flowing between the walls is the product between the current and the time interval:

The problem says

, so the total charge is

The current consists of Na+ ions, each of them having a charge of

. To find the number of ions flowing, we can simply divide the total charge by the charge of a single ion: