In a downhill ski race, your final velocity is not affected very much by getting a running start, because the initial kinetic energy is small compared with the gain in gravitational potential energy on even small hills. However, you will finish the race much faster (which is more important!). To demonstrate this, find the final speed and the time taken for a skier who skies 72.5 m along a slope that is 23°, measured from horizontal, in the following situations (you may neglect friction).

a) Find the final speed (in m/s) of the skier starting from rest.
b) How long (in s) does it take for the skier to reach the bottom of this hill starting from rest?
c) Find the final speed (in m/s) of the skier starting with a speed of 2.50 m/s.
d)How long (in s) does it take for the skier to reach the bottom of this hill with a starting speed of 2.50 m/s?