Here are the steps to solve this problem using the midpoint method:
(a) Calculate the midpoint of the price and quantity demanded for each row when income is $10,000:
$8 and 40 DVDs => Midpoint = 24 DVDs
$10 and 32 DVDs => Midpoint = 31 DVDs
$12 and 24 DVDs => Midpoint = 27 DVDs
$14 and 16 DVDs => Midpoint = 16 DVDs
$16 and 8 DVDs => Midpoint = 12 DVDs
(b) Plot the midpoints on a graph with Price on the y-axis and Quantity Demanded on the x-axis. Connect the points to draw the demand curve when income