How heavy a load (pounds) is needed to pull apart pieces of douglas

How heavy a load (pounds) is needed to pull apart pieces of douglasQuestions How heavy a load (pounds) is needed to pull apart pieces   of Douglas fir 4in long and 1.5 inches square?  Here are the data   from students doing a laboratory exercise:  33,190  31,300 32,320  26,520 23,040  30,460 24,050  33,650 31,860  28,730 33,020  33,280 30,930  32,700 30,170  32,340 32,590  31,920 32,030 32,720  A)  We   are willing to regard the wood pieces prepared for the lab session as an SRS   of all similar pieces of Douglas fir.  Engineers also commonly   assume that characteristics of materials vary Normally.  Make a   graph to show the shape of the distribution for these data.  Does   the Normality condition appear safe?  Suppose that the strength of   pieces of wood like these follows a Normal distribution with standard   deviation 3000 pounds. B)  Give   a 90% confidence Interval for the mean load required to pull the wood apart.