Who discovered Hooke's law?

According to Hooke's law; Force is equal to -

If the original length of a spring is 20m and its extended length is 30m. What is the extension?

A bungee rope has a spring constant of 5N/m. How much a person must weighs in Newton if we want it to extend (stretch) 10m?

What is the spring constant of a bungee rope in N/m if a person weighs 100 N if we want it to extend (stretch) 20m?

If a bungee rope has a spring constant of 10 N/m. How far will it extend (stretch) if a person who weighs 300 N is placed on it?

___________ is the unit of force

________________ force acts on an object when it falls.

__________________ is the force acting on two rubbing hands