Listed below are the amounts of mercury in parts per million

Listed below are the amounts of mercury (in parts per million, or ppm) found in tuna sushi sampled at different stores. The sample mean is 1.120 ppm and the sample standard deviation is 0.277 ppm. Use technology to construct a 90% confidence interval estimate of the mean amount of mercury in the population. What is the confidence interval estimate of the mean amount of mercury in the population?