I think the answer is wind
Answer:
The radius is
Explanation:
From the question we are told that
The speed at which the race car moves is 
The centripetal acceleration is 
Generally the centripetal acceleration is mathematically represented as

=> 
=>
Answer:
The net gravitational force on the mass is 
Explanation:
We have by Newton's law of gravity the force of attraction between masses 

Applying vales we get
Force of attraction between 135 kg mass and 38 kg mass is

Force of attraction between 435 kg mass and 38 kg mass is

Thus the net force on mass 38.0 kg is 
Answer:
The centripetal acceleration of car is 8 m/s².
Explanation: