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You wish to estimate with 98% confidence the population proportion of PCC students who have a 3.5 GPA and higher. Your estimate must be accurate within 2% of the population proportion.

a) No preliminary estimate is available. Find the minimum sample size needed?

b) Find the minimum sample size needed, using a prior study that found 47% of PCC students have 3.5 GPA or higher.

c) Compare your results for (a) and (b). Interpret the difference in the results.