the bars is in perfect adjustment. 10. A random sample of 48 days take at a large hospital shows that averages of 38 patients were treated in the emergency room [ER) per day. The standard deviation of the population is four. Find the 9936 confidence interval of the mean number of BR patients treated each day at the hospital. 11 A machine produces metal rods used in an automobile suspension system. A random sample of 10 rods was selected, and diameter was measured. The resulting data in millimeter is shown in Table 9. Table 9 8.23 8.30 8.27 8.27 6.29 839 8.21 8.36 Find the 909% confidence interval of the meun rod diameter. 12 The thickness of blended osment for waterproofing application has a nomal distribution. 25 samples of blended cement for water proofing application were selected randomly and have = mean of 1.17 om and a standard deviation of 0.32 om. Determine the standard error of estimate if @= 0.08 . Find the 9836 confidence interval of the mean thickness of blended cement for waterproofing application. Find the 903% confidence interval of the mean thickness of blended cement for waterproofing application. Is there any difference between the result in question (b) and ko)? why