For Exercises 17 and 18, let y = P(t) denote the percentage of U.S. households in th...

For Exercises 17 and 18, let y = P(t) denote the percentage of U.S. households in the year t with at least one VCR (video cassette recorder). The following figure shows a graph of this function P over the period

(a) In the given graph (or in a photocopy), use a ruler to draw two line segments, one connecting the two points (1978, P(1978)) and (1988, P(1988)), the other connecting the two points (1984, P(1984)) and (1997, P(1997)). You’ll find that the two line segments appear to be parallel (or nearly so). Now complete the following sentence (concerning on the two intervals Because parallel lines have equal slopes, we can estimate that _____________________________________.

(b) Using the following data, compute for each of the two periods mentioned in part (a). Round the answers to one decimal place. Do your answers support the estimate you made in part (a)?

(c) Can you explain the downturn after 2000?