Answer:
The work done on the athlete is approximately 2.09 J
Explanation:
From the definition of the work done by a variable force:

and substituting with the function of our problem:

Answer:

Explanation:
For sound waves we have v=d/t where v is the speed of sound and d the distance between the astronauts, while for electromagnetic waves we have c=D/t where c is the speed of light and D the distance between the spaceship and Earth. <em>We have written both times as the same</em> because is what is imposed by the problem, so we have t=d/v=D/c, which means:

And for our values:

Thermal energy is the answer
Hope that helps