The answer they are looking for is the last one. However the last two are technically correct but the third one would result in negative work.
The measure of the quantity of matter would be mass. Mass is measured in kilograms. I hope this helped!:)
Explanation:
Given that,
Initial speed of the sports car, u = 80 km/h = 22.22 m/s
Final speed of the runner, v = 0
Distance covered by the sports car, d = 80 km = 80000 m
Let a is the acceleration of the sports car. It can be calculated using third equation of motion as :




Value of g, 


Hence, this is required solution.
Explanation:
It is given that,
A mass oscillates up and down on a vertical spring with an amplitude of 3 cm and a period of 2 s. It is a case of simple harmonic motion. If the amplitude of a wave is T seconds, then the distance cover by that object is 4 times the amplitude.
In 2 seconds, distance covered by the mass is 12 cm.
In 1 seconds, distance covered by the mass is 6 cm
So, in 16 seconds, distance covered by the mass is 96 cm
So, the distance covered by the mass in 16 seconds is 96 cm. Hence, this is the required solution.