Answer:
900 lb to the right
Explanation:
Newton's third law of motion states that for every action there is equal and opposite reaction.
Hence if the two cars (i.e. car A and car B) crash head on and there is an impact on car A of 900 lb to the left, car B would have to generate a force of equal magnitude and in an opposite direction. Since car A had a force of 900 lb to the left, the impact force exerted on car B would be 900 lb to the right.
The answer is 900 lb to the right