1. If a and b are both odd numbers, then which of the following must be an odd number ?   a + b   ab + 1   ab   2a + b + 1   a + b + 2   Hint Half-n-half Clue   2. If a line segment is drawn connecting point A (-4, 8) and point B (14, -22), then the coordinates of the midpoint are   (5, -7)   (-7, 5)   (18, -30)   (-30, 18)   (10, -14)   Half-n-half Clue   3. There are 720  animals on a farm. Three-fourths of them are cows. Of the cows, about 90% are white. How many cows on the farm are not white?   486   53   540   180   71   Half-n-half Clue   4. A piece of equipment consumes c cents per hour of fuel and requires d dollars per hour for other operational costs. What is the cost in dollars of operating the equipment for 1000  hours?   1000 c + 10 d   10 c + 1000 d   1000 (c + d)   0.01 c + d   10 (c + d)   Half-n-half Clue