The following table shows worldwide sales of cell phones by a certain company and their average wholesale prices in the first quarters of 2009 and 2010.

92	88
110	118

(a) Use the data to obtain a linear demand function for the company's cell phones. (Letpbe the price, and letqbe the demand).

q(p) =

Use your demand equation to predict sales if the company lowered the price further to$80.

________million phones

(b) Fill in the blank. For every $1 increase in price, sales of cell phones decrease by________million units.