The sales of a new high~tech item (in thousands) are given by smztioQOe'O-Z' 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 '1 thousand items per year. (Round to three decimal places as needed.) '0. The rate of change after 5 years is D thousand items per year. (Round to three decimal places as needed.) c. What is happening to the rate of change of sales as time goes on? O A. it always increases. 0 B. First it increases, then it decreases. O C. it always decreases. O D. First it decreases, then it increases. d. Does the rate of change of sales ever equal zero? 0 No 0 Yes