A researcher wanted to know the percentage of the urban population that had ever experienced depression in the past month. He randomly sampled 500 adults in a big city. He found that 12 percent to 20 percent of the adults had experienced any type of depression in the past month. What was the width of the confidence interval (as a percent)?

Question 3 options:

	(20-12) = 8 percent
	12 percent
	(20-12)/2 = 4 percent
	20 percent