1) 4 pts.
6 things to put in order
4(the longest chain that was correct / 6)

2, 3) 2 pts each part.
Were supposed to be proofs, using the definition.
2, 1, or 0 points.
2 - used the definition correctly
 a) on #2 - give constant c and n0
 b) use the limit definition

Note, for problem 3, first you are given a constant c.  It could be 
really big, but constant.  Then you have solve for n0 so that 
f(n) <= c*g(n) for every n >= n0.