In a study of government financial aid for college? students, it becomes necessary to estimate the percentage of? full-time college students who earn a? bachelor's degree in four years or less. Find the sample size needed to estimate that percentage. Use a 0.05 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 45% of? full-time students earn? 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 effect on the sample? size?

A. ?No, using the additional survey information from part? (b) only slightly reduces the sample size.

B. ?Yes, using the additional survey information from part? (b) dramatically reduces the sample size.

C. ?Yes, using the additional survey information from part? (b) only slightly increases the sample size.

D. ?No, using the additional survey information from part? (b) does not change the sample size.