Question

laptop computers are made with batteries, but they must also be plugged into outlets to charge the batteries. which is true regarding laptops?
they run only on alternating current.
they run only on direct current.
they can run on either direct or alternating current.
they do not run on direct or alternating current.

Explanation:

1. First, recall the types of current: Alternating Current (AC) is from wall outlets, and Direct Current (DC) is from batteries (like laptop batteries).
2. Laptops are plugged into outlets (AC) to charge the battery, and when using the battery, they run on DC from the battery. So they can use either: when plugged in, they can run on AC (while also charging the battery) or on DC from the battery when not plugged in (or even when plugged in, some laptops can switch). The other options are incorrect: they don't run only on AC (battery is DC), not only on DC (they can use AC when plugged), and they do run on these currents.

Answer:

They can run on either direct or alternating current.