Several inventions are listed in Table 18, along with the years they were invented and how long it took for one-quarter of the U.S. population to use them (€œmass use€).

Let M be the number of years elapsed until an invention reached mass use if it was invented at t years since 1870.
a. Construct a scatterplot.
b. Is the association positive, negative, or neither? What does that mean in this situation? In your opinion, why does that make sense?
c. Does the point for the microwave oven fit the overall pattern you described in part (b)? Explain.
d. For a while after the microwave oven was invented, many people feared it would cause radiation poisoning, blindness, or impotence. Discuss the impact of these fears in terms of your response to part (c).
e. Explain why the point for the gasoline-powered automobile does not fit the overall pattern you described in part (b). Why do you think this happened? We say that the point is an outlier.

Table 18 Number of Years until Inventions Reached Mass Use Year Invented 1873 1876 1886 1897 923 1953 1965 1975 1985 1985 1991 1997 Years until Mass Use 46 35 Invention Electricity Telephone Gasoline-Powered Automobile Radio Television Microwave Oven VCR Personal Computer Mobile Phone CD Player World Wide Web DVD Player 31 29 13 16