The Quality Control Manager of a Tire Company Wishes to Estimate

The quality control manager of a tire company wishes to estimate the tensile strength of a standard size of rubber used to make a class of radial tires.A random sample of 61 pieces of rubber from different production batches is subjected to a stress test.The test measures the force (in pounds) needed to break the rubber.According to the sample results,the average pressure is 238.4 pounds with a population standard deviation of 35 pounds.Determine the 98 percent confidence interval.

A) [227.96,248.82]
B) [236.64,240.16]
C) [233.63,243.17]
D) [229.21,247.59]