For this problem, carry at least four digits after the decimal in your calculations. Answers may vary slightly due to rounding. In a marketing survey, a random sample of 996 supermarket shoppers revealed that 264 always stock up on an item when they find that item at a real bargain price. (a) Let p represent the proportion of all supermarket shoppers who always stock up on an item when they find a real bargain. Find a point estimate for p. (Enter a number. Round your answer to four decimal places.) (b) Find a 95% confidence interval for p. (For each answer, enter a number. Round your answers to three decimal places.) lower limit upper limit