Osmar Ltd conducted a study to determine the lifetimes of the light bulbs produced by their Melbourne plant. Based on studies in other plants, it could be assumed that the variance of the lifetimes was80000 hours squared. Experimental testing of57 light bulbs yielded an average lifetime of 23 hundredhours. Construct a 90% confidence interval for the average lifetime of the bulbs produced in Osmar's Melbourne plant. Report the lower limit in hoursto 1 decimal place.