Answer:
Explanation:
Sum all the forces that are acting on the object and what ever the sum is, is what the net force is.
For example if there is a piece of wood sitting on a table the net force would be the sum of the forces that are acting on it, so the force of gravity (which is negative) + the normal force which would equal zero because they are the same value.
The first two choices are both false, but the <em>second one</em> is the falser one.
All electricity sources do <em>not</em> have the same voltage. The outlet in your bedroom wall supplies 120 volts, but the USB port on your laptop only supplies 5 volts, and the battery in your cellphone only supplies 3.7 volts.