What is the average momentum of a 70-kg runner who covers 400 m in 50 s?

560 kg m/s

Explanation:

First of all, we have to find the velocity of the runner, which is given by  the ratio between the distance covered (400 m) and the time taken (50 s):

And now we can calculate the average momentum of the runner, which is equal to the product between the mass of the runner (70 kg) and its velocity, that we have previously calculated:

your answer is c! hope this : )

see the picture for the vector

the magnitude of the vector by pythagorean theorem

r = √( (-10)^2 + (3)^2 ) = √109

magnitude = √109 units

the direction angle between vector and x-axis is

tan^(-1)(3/10) = 16.699

so the direction is approximately 16.7 degrees north of west