The energy that the student shoud use in order to climb the stairs is equal to its increase in gravitational potential energy:

where m is the mass of the student, g the gravitational acceleration and

the variation of height. Plugging numbers into the equation, we find

The power required for the student to climb the stairs is equal to the work done divided by the time taken:

**Answer:**

Resistance

**Explanation:**

Resistance "resists" the flow of electricity and makes it more difficult to travel. The higher the resistance the less current there is in a circuit. Example being, open circuit (infinity ohms) means there is no current flowing with ohms law.

The answer to this question is 2400Hz