Wildlife biologists inspect 153 deer taken by hunters and find 32 of them carrying ticks that test

Question:

Wildlife biologists inspect 153 deer taken by hunters and find 32 of them carrying ticks that test positive for Lyme disease.
a) Create a 90% confidence interval for the percentage of deer that may carry such ticks.
b) If the scientists want to cut the margin of error in half, how many deer must they inspect?
c) What concerns do you have about this sample?