What would the coefficient of friction be if the frictional force was equal to the normal force? (answer will be an number)

Write a full page that sumerizes thermodynamics it’s from the website visionlearnig

During a medieval siege of a castle, the attacking army uses a trebuchet to hurl heavy stones at the castle walls. if the trebuchet launches the stones with a velocity of at an angle of 50.0°, (a) how long does it take the stone to hit the ground? (b) what is the maximum distance that the trebuchet can be from the castle wall to be in range? (c) how high will the stones go? show all your work.

I’ve been stuck on this for a while