What is the x= ? how do you get the margin of error at 90%? Then the 90% confidence interval?

Start Suppose the mean height in inches of all 9th grade students at one high school is estimated. The population standard deviation is 4 inches. The heights of 7 randomly selected students are 63, 63, 67, 60, 74, 75 and 67 = Ex: 12.34 Margin of error at 90% confidence level = Ex: 1.23 90% confidence interval = [ Ex: 12.34 Ex: 12.34 1 [smaller value, larger value]