Answer:
B
Explanation:
Potential difference has a SI Unit of Volt and its symbol is <em>V</em>. Hence answer is <u>B</u>.
A is wrong as it has the unit Joule <em>(J)</em> which is the SI unit for energy.
C is wrong as it has the unit Newton <em>(N)</em> which is the SI unit for force.
D is wrong as it has the unit Coulomb <em>(C)</em> which is the SI unit of charge.
To find average speed, we divide the distance of travel (in this case, 400 metres) by the time she took, 32 seconds. Therefore: 12.5 seconds is her average speed.
Proceed with caution before crossing
Average speed=total distance travelled/time
