Awindmill’s blades move from the blowing wind. the movement of the blades represents

Kinetic energy

Explanation:

The windmill’s blade was in a state of rest. Any object in a state of rest possesses potential energy which is given as mgh. The wind however blows and the blades move.

The wind helps in the conversion of the potential energy at rest to kinetic energy when in motion. The kinetic energy is given as 1/2* mass * the square of the velocity.

b. lifting dumbbell weight at 20-degree angle from the body after a 45-degree angle