Questionwww. helpyourmath.com is an OER website to help students to save money on textbooks and homework systems. A survey of 24 randomly selected students finds that they save a mean of $\$ 86$ per semester by using www.helpyourmath.com. Assume the date comes from a normal distribution and the sample standard deviation is $\$ 19$ per month.
Confidence Interval: What is the $95 \%$ confidence interval to estimate the population mean? Round your answers to two decimal places. $\square$