A stock market investment of $18,000 was made in 1970. During the decade of the 1970s, the stock lost half its value. Beginning in 1980, the value increased until it reached $34,000 in 1990. After that its value has remained stable. Let
v = v(d)
denote the value of the stock, in dollars, as a function of the date d.
(a) What are the values of v(1970), v(1980), v(1990), and v(2010)? (b) Make a graph of v against d.
(c) Estimate the time when your graph indicates that the value of the stock was most rapidly increasing.