PRACTICE EXAM 1 - SAMPLE ANSWERS

1. (a) C, D, B, E, A
   (b) E, D
   (c) 12, 17, 25
   (d) 8
   (e) 38 - <<< CORRECTION!!!
   (f) The rise of email has led to a huge decrease in postal mail.
   (g) C, 7, N

2. (a) 15, 9, 9, 18, 0
   (b) def cone_volume(height, radius)
           return Math::PI * radius * radius * height / 3
       end
   (c) print cone_volume(10,4) + cone_volume(5,6) + cone_volume(7,2)
   (d) j   1   4   9  16  25
       k   3   5   7   9  11
   (e) The square of n
   (f) Since mystery doesn't return anything, you can't add the
       results of three of these function calls.

3. (a) "apple"
       7
       "peach"
       false
       cherry banana orange
       ["peach", "grape", "orange", "melon"]
   (b) numlist        primes
       [3,5,7,9]      [2]
       [5,7]          [2,3]

4. (a) list[0]
       1..list.length-1
       list[i]
       min_so_far = list[i]
       min_so_far
   (b) list.first, list.length == 1
       list[1..list.length-1]
       list.first < min_without_first_element
   (c) The function calls itself.

5. (a) list.length-1
       i >= 0
       nil
   (b) O(n)
   (c) FALSE
   (d) [3, 8, 7, 4, 5]
       [3, 4, 7, 8, 5]
       [3, 4, 5, 8, 7]
       [3, 4, 5, 7, 8]
   (e) c  (both are O(n**2) in the worst case)