•5. How many suns would it take, laid edge to edge, to reach the nearest star? 
 •
 •Basically, all you have to do here is divide
 the distance by the diameter of the sun. 
 The distance is 4.28 light-years (table A-7).  Convert to meters by multiplying
 by 9.46x1015m per light-year (table
 A-6).  The diameter of the sun is 2 x radius = 14x108m (table A-6).  So, the number of suns is 4 x 1016 m/14 x
 108 m = 2.9 x 107 m.