An inferior product with an extensive advertising campaign does well when it is released, but sales decline as people discontinue use of the product. If the sales S (in thousands of dollars) after t weeks are given by

what is the rate of change of sales when t = 10? (Round your answer to two decimal places.) ) = .
Interpret your result.
a. From the 10th to the 11th week, sales will decrease approximately dollars.
b. From the 10th to the 11th week, sales will increase approximately thousand dollars.
c. From the 10th to the 11th week, sales will increase approximately dollars.
d. From the 10th to the 11th week, sales will decrease approximately l thousand dollars.