Answer:
The margin of error is of 20, option B.
Step-by-step explanation:
Confidence interval concepts:
A confidence interval has two bounds, a lower bound and an upper bound.
A confidence interval is symmetric, which means that the point estimate used is the mid point between these two bounds, that is, the mean of the two bounds.
The margin of error is the subtraction between the bounds, divided by 2.
In this question:
Lower bound: 200
Upper bound: 240
Margin of error:
(240 - 200)/2 = 40/2 = 20
The margin of error is of 20, option B.
