Based on the output above, we find that out of 1032 passengers, 277 are in the middle-class. What is the margin of error of a 95% confidence interval for the percentage of middle-class passengers? a) 0.027 b) 0.036 c) 0.023 d) 0.018

	Passenger Class
sex	1	2	3
female	144	106	216
male	179	171	493