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In a study of government financial aid for college students, il becomes necessary to estimate the percentage of full-time college students who earn a bachelor's degree in four years of less. Find the sample size needed to estimate that percentage Use a 3.02 margin of error and use a confidence level of 90%. Complete parts (a) through (c) below a. Assume that nothing is known about the percentage to be estimated. (Round up to the nearest integer.) b. Assume prior studies have shown that about 40% of full time students carn bachelor's degrees in four years or less (Round up to the nearest integer) c. Does the added knowledge in part (b; have much of an clfect on the sample size? O A. No, using the additional survey information from pan (o) does not change the sample size O B. Yes, using the additional survey information from part () only sighty increases the sample size O C. No, using the additional survey information from part (o) only slightly reduces the sample size. O D. Yes using the additional survey information from part (b) dramatically reduces the sample size