Question: Total blood volume per body weight is important in medical research. For healthy adults, the red blood cell volume mean is about μ=28 ml/kg. Red blood cell volume that is too low or too high can indicate a medical problem. Suppose that Roger has had seven blood tests and the red blood cell volumes were

32 25 41 35 30 37 29

The sample mean is x ≈ 32.7 ml/kg. Let x be a random variable that represents Roger's red blood cell volume. Assume that x has a normal distribution and ? = 4.75. Do the data indicate that Roger's red blood cell volume is different (either way) from μ = 28 ml/kg? Use a 0.01 level of significance.