The sales of a new high-tech item (in thousands) are given by
S(t) = 91 - 80
-0.41
where t represents time in years. Find the rate of change of sales at each time.
a.) After 1 year. b.) After 5 years. c.) What is happening to the rate of change of sales as time goes on? d.) Does the rate of change of sales ever equal zero?
.
a. The rate of change after 1 year is thousand items per year.
(Round to three decimal places as needed.)

How do water’s relative densities as a solid and a liquid differ from that of most other substances? water’s solid and liquid forms have different densities, while most other substances have solid and liquid forms with similar densities. water’s solid and liquid forms have similar densities, while most other substances have solid and liquid forms with different densities. water’s liquid form is less dense than its solid form, while the opposite is true of most other substances. water’s solid form is less dense than its liquid form, while the opposite is true of most other substances.