Marking scheme for COSC2001 Assignment 2:

Q1.  1 for giving right answer ("no")
     4 for proof.
     (If you answered "yes", you get 0/5 for this question.)

Q2.  4 marks.
     You don't have to give an explanation of why it works if it is obvious.
     If it's less than obvious, an explanation should be provided.

Q3.  (a) 4 marks
     (b) 3 marks
     (c) 3 marks

Q4.  4 marks

Q5.  3 marks

Q6.  3 marks for giving a construction that works.
     2 marks for some explanation of why it proves what they
     are supposed to prove.

Total 31.