A student runs around a 400 m oval track in 80 s. Would the average velocity and average speed be the same? Explain?4

No, the speed and velocity would be different in this case.

Explanation:

As we know that speed is the distance covered by a body per unit time and velocity is the displacement per unit time.

Displacement is the shortest distance between the final and the initial points.

In an oval path the distance is the path traced on the periphery of the oval track and its displacement will be the shortest distance between the final and initial position of the runner, i.e. the straight line joining the final and the initial position.

Displacement will always be lesser than the distance here and hence the velocity will always be smaller than the speed.

b.

explanation:

when jerome paddle in flowing river towards east the net speed of jerome will increase

so the net speed of jerome will be given as

now the speed of paul will be same as it is given as he is running on the ground

so

so here we can say since the speed of jerome is more so he will win the race

now as we know the distance so the time difference is given as

so jerome will reach first and the time difference will be 203.55 s or 3.4 min