78 65 The following data give the speeds (mph) as measured by radar of 10 cars traveling on a certain highway: 76 72 80 68 76 74 71 82 Assuming that the speeds of all cars traveling on this highway have a normal distribution. What is the point estimate of population mean? Construct a 90% confidence interval for the mean speed of all cars traveling on this highway? 3. Use hypothesis test to check the claim that the mean speed of cars is 75 mph.​