Given:
p = 20% = 0.2, sample proportion
n = 5000, sample size.
Confidence level = 95%
The confidence interval is
(p - 1.96k, p + 1.96k)
where

Therefore the 95% confidence interval is
(0.1943, 0.2057) = (19.4%, 20.6%)
Answer: The 95% confidence interval is (19.4%, 20.6%)
Arc tan ( 1/√3 ) = arc tan ( √3/3 ) = 30°
180° = π ( in radians )
30° = 180°/6 = π/6
18 |16 | 13 | 10 | 9.5 | 8.5 | 7.5 | 6
9.75 is the FINAL answer