Q3: Interval guess Many cardiac patients wear implanted pacemakers to control their heartbeat. A plastic connector module mounts on the top of the pacemaker. Assuming a normal distribution with a standard deviation of 0.0015 is considered. a) Find a 93% C.I. for the population mean of all connector modules made by a certain manufacturing company, based on a random sample of 75 modules with an average of 0.310 inch. b) How many data should we collect if we wish to have 0.97 confidence level that our sample mean will be within 0.0005 inch of the population mean