29. A sample of n = 10 scores has a mean of M = 15. One person with a score of 13 is added to the sample. What is the new value of the sample mean? [ Select ] 30. A researcher collects two samples. The first sample has n1 = 7 scores has a mean of M, = 3. The second sample has n2= 3 scores has a mean of M2 = 7. What is the mean of the combined samples? [ Select ]