5. Suppose a random sample of 1500 registered voters was surveyed about energy issues. (a) If 230 of the 1500 responded that they would favor drilling for oil in national parks, estimate the proportion 39 of registered voters who would favor drilling for oil in national parks. Construct a 95% condence interval, provide its interpretation in the context of the problem and verify the respective assumptions that validate the use of a normal approximation. (b) How many persons must the survey include to have a 95% condence interval with a margin of error of less than 1% for p? (c) A congressman has claimed that the majority of all registered voters would support drilling in national parks. Use the survey data to evaluate the congressman's claim. Use a: : 0.05 for the test