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:

i'm thinking more like energy

depends on what you mean by "group." for order, it would be coleoptera (beetles). for class, it would be insecta (insects). for phylum, it would be the arthropoda (animals with jointed exoskeletons).

explanation: