(a) Using Kepler's third law, p^2 = Kr^3.  For our solar system, we know already
that K = 1 if p is measured in years and r is measured in AU.  So, the orbital 
period of Jupiter around the Sun is

   p = sqrt( 1 * 5.2 * 5.2 * 5.2) = 12 years.  

Going from the near side of the Sun-Jupiter system to the far side would take half 
an orbit, so the time required would be about 6 years.


(b) v = r/t, and from Exercise 1, Part (c) above, we know that r = 1.5 * 10^6 km.

The time, in seconds, is about

  (6 yr) * (525,600 min/yr) * (60 sec/min) = 1.9 * 10^8 s.

So the average velocity during this motion of Jupiter would be

  (1.5 * 10^6 km) / (1.9 * 10^8 s) = 0.0079 km/s.


(c) How fast does a human being run?  In the Olympics, we often hear of sprinters
running the 100-meter dash in about 10 seconds.  These sprinters are thus going
about (100 m)/(10 s) = 10 m/s, or 0.01 km/s.  This is 0.0021 km/s faster than 
the velocity of the motion calculated in Part (b) above; so for short distances,
a person could actually outrun the motion of our solar system's center of mass.