This is false. There were many times in history when people discovered something that they didn't even know was possible or didn't even plan to discover it. Knowing tradeoffs doesn't mean that something won't surprise you or that all will go according to plan.
Answer:B
Explanation:
Given
speed of car 
mass of clump 
Radius of car tire 
Since the tire is rotating about axle so a centripetal force is acting constantly on each particle towards the center of tire.
Centripetal force is given by

where 



(inward)
Answer:
Due to the resistance of air, a drag force acts on a falling body (parachute) to slow down its motion. Without air resistance, or drag, objects would continue to increase speed until they hit the ground. The larger the object, the greater its air resistance. Parachutes use a large canopy to increase air resistance. Also, Once the parachute is opened, the air resistance overwhelms the downward force of gravity. The net force and the acceleration on the falling skydiver is upward. An upward net force on a downward falling object would cause that object to slow down. The skydiver thus slows down. Sorry if not helpful.