In Table A4, x represents the number of umbrellas sold per month, y represents the price of an umbrella, and z repre- sents the average number of rainy days per month. TABLE A4 Umbrellas Sold Price per Average Number of per Month Umbrella Rainy Days per Month (x) (2) 120 $10 4 140 $10 5 160 $10 6 100 $12 4 120 $12 5 140 $12 80 $14 4 100 $14 5 120 $14 6

a. Using the grid below, on the same diagram, graph the relationship between x (horizontal axis) and y (vertical axis) when 4, when 2-5, and when: -6. h. On average, it rains six days per month. This implies a certain average relationship between monthly umbrella sales and umbrella price. Suppose that the "greenhouse effect" reduces the average monthly rainfall to four days per month. What happens to the graph of the relationship between umbrella sales and umbrella prices?

e. Using the grid below, graph the relationship between x (horizontal axis) and z (vertical axis) when y$10 and when y $12. Is the relationship between x and positive or negative?

d. Using the grid below, graph the relationship between y (horizontal axis) and (vertical axis) when x = 120 and when x