Use the following miof You are planning to conduct a poll of community members age 65 and older, to determine how many own mobile phones. You want to produce an estimate whose 95% confidence interval will be within four percentage points (plus or minus) the true population proportion. Use an estimated population proportion of 0.5. or blucher summ andw :001 of sxia slamse ords beansnoni nov 1 21 20. Suppose you knew from prior research that the population proportion was 0.6. What sample size would you need