Suppose that we interviewed a random sample of 2000 people and found that 320 of them smoke regularly. Find the 90% confidence interval for the population proportion of smokers.
a) 0.148 ≤ p ≤ 0.182
b) 0.155 ≤ p ≤ 0.175
c) 0.160 ≤ p ≤ 0.170
d) 0.145 ≤ p ≤ 0.185
