The percent P of households in the United States with wireless-only telephone service from 2005 through 2014 can be approximated by the model P = −3.42 + 1.297t ln t, 5 ≤ t ≤ 14 where t represents the year, with t = 5 corresponding to 2005. (Source: National Center for Health Statistics)
(a) Approximate the percents of households with wireless-only telephone service in 2008 and 2012.
(b) Use a graphing utility to graph the function.
(c) Can the model be used to predict the percent of households with wireless-only telephone service in 2020? in 2030? Explain.