Does anyone know what to put for the question in red :/, (ps her fact sheet is no help)

Awind turbine is rotating counterclockwise at 0.5 rev/s and slows to a stop in 10 s. its blades are 20 m in length. (a) what is the angular acceleration of the turbine? (b) what is the centripetal acceleration of the tip of the blades at t=0s? (c) what is the magnitude and direction of the total linear acceleration of the tip of the blades at t=0s?

For waves in the ocean, the medium of the waves is a. air b. water c. energy d. a passing boat

What is a subatomic particle with a negative charge and very little mass?