One important thing that the government looks at when allowing funds for financial aid is the proportion of students that would graduate with a bachelor's degree in 4 years or less, (15 units per...

One important thing that the government looks at when allowing funds for financial aid is the proportion of students that would graduate with a bachelor's degree in 4 years or less, (15 units per semester) Find the sample size needed to estimate that proportion.

For this problem use a confidence level of 90% and a margin of error of 2%

i) find the sample sie when nothing is known about the percentage to be estimated.

ii) Now find the sample size assuming studies have shown that 45% of all students earn their degrees in four years.