A sample survey is designed to estimate the proportion of sports utility vehicles being driven in the state of California. A landom sample of 500 registrations are selected from a Department of Motor Vehicles database, and 62 are classified as sports utility vehicles. (a) Use a 95% condence interval to estimate the proportion of sports utility vehicles in California. [Round your answers to three decimal places.) |:|t|:l (b) How can you estimate the proportion of sports utility vehicles in California with a higher degree of accuracy? (HINT: There are two answers. Select all that apply.) :1 increase 2 by decreasing the condence coefficient ml: 3 decrease the sample size n 3 increase the sample size n 3 decrease Zita\"! by decreasing the oonfidence coefficient 3 increase emf: by increasing the confidence coefficient 3 decrease Zita\"! by increasing the condence coefficient j conduct a non-random sample You may need to use the appropriate appendix table or technology to answer this question. 215 Points] MEN DSTATlnI- 8.E.081. ASK YOUR TEACHER Suppose you wish to estimate the difference between the mean acldity fur minfalls at two different locations, one in a relatively unpolluted area and the other in an area subject to heavy air pollution. If you wish your estimate to be correct to the nearest 0.2 pHr with probability near 0.90. approximately hDW many lainfalls [pH values} would have to be included in each sample? (Assume that the Variance of the pH measurements is approximately 0.2 at both locations and that the samples will be of equal size. Round your answer up to the nearest whole number.) WEHFHS You may need to use the appropriate appendix table or technology to answer this