Quiz Stuff

• Use a full sheet of 8½ x 11" paper. (Half sheet? Half credit!)
• Put your last name and first initial in the far upper left hand corner!
  
• No need to write out questions.
• Numbering responses may help you avoid overlooking a question; it's ok to go ahead and pre-number your sheet.
• Time: 4 minutes; three questions worth 3, 2, and 1 points respectively.

Quiz 9; March 20; Time: 4 minutes; 3+2+1 points

1. Write a predicate three(?N) that if called with 3, it succeeds. If called with an uninstantiated variable, it instantiates the variable to 3. If called with a value other than 3, it fails.

   ?- three(3).
   true.
   ?- three(X).
   X = 3.
   ?- three(5).
   false.
   

2. Write a predicate gt10(+X,+Y) that succeeds iff the sum of X and Y is greater than 10. X and Y are assumed to be instantiated.

   ?- gt10(8,5).
   true.
   

3. Does the following query succeed, or does it fail? (No need to explain why.)

   ?- three(A), three(B), C is A*B, gt10(C,C).