Need some with this physics question?
a new car model is described as having 340 horsepower. at this horsepower, the car’s engine produces 900 kilowatts of heat as it operates. what is the engine’s efficiency?
a) 22%
b) 28%
c) 37%
d) 46%

The only piece of information you need that the question doesn't tell you is:

1 horsepower = 746 watts

So 340 horsepower = 253,640 watts

-- The output of the engine is 253.640 kW useful energy and 900 kW waste heat.

-- The engine is using 1,153.640 kW total energy.

-- The useful output is 253.640 kW.

-- Efficiency is (253.640 kW) / (1,153.640 kW)

Efficiency = 21.99 %

what was the acceleration of the 2 kg cart?

⇒ 16.0 cm/s2

what was the acceleration of the 4 kg cart?

⇒ 8.1 cm/s2

what was the acceleration of the 6 kg cart?

⇒ 5.3 cm/s2

ammonium chloride & tallow