4. The mean productivity rating for all employees at a company was 3.8 on a five point scale last year. This year you get ratings from a representative sample of fifteen employees from the Human Research Management. Do the data from this sample provide evidence that employee productivity in the department of Human Resource Management is significantly higher than in the company as a whole? Scores: 4.1, 3.9, 3.5, 4.0, 4.4, 4.3, 4.2, 4.5, 3.9, 3.6, 4.2, 4.4, 4.1, 4.3, 4.25. An investigator believes that young adults have better accuracy recognizing young adults than children. The investigator conducts a study on 19 young adults by showing them a series of photographs and later testing their recognition accuracy. Below are the accuracies for each participant for both the children photographs and young adult photographs. Is the investigator's theory correct? Children Young Adult 65 80 67 69 53 70 65 70 67 60 57 74 69 65 61 63 69 65 67 70 56 80 65 79 57 69 63 75 53 62 58 73 55 71 61 68 66 756. A study was performed to test whether cars get better mileage on premium gas than on regular gas. Each of 6 cars was first filled with either regular or premium gas, decided by a coin toss, and the mileage for that tank was recorded. The mileage was recorded again for the same cars using the other kind of gasoline. Is there evidence that the using premium gasoline is better? Regular = (16, 20, 21, 23, 22, 28) Premium = (19, 22, 24, 25, 25, 32)