Difference between two proportions

In the Mediterranean sea, 600 brills were captured and dissected and 216 were found to be infected by a parasite. In the Atlantic Ocean, 120 brills were captured and dissected and 24 were found to be infected.

(a) Construct a 90% confidence interval for comparing the proportions of infected brills in the two captured sites

(b) Test whether the proportion of infected brills at the Mediterranean sea is higher that at the Atlantic Ocean