There has been a considerable underfunding of the national Highway Trust Fund over the last 20 years which has resulted in a dramatic decline in the maintenance of the nation's roads and bridges. An organization representing highway construction companies is planning a nationwide survey to estimate the proportion of people who would support an increase in gasoline tax. How large a sample is needed to obtain an estimate of to within 0.02 using a 95% confidence interval. Consider two situations:

a. suppose the organization has no idea of .

b. Suppose the organization is fairly certain that is greater than 70%.