a. A population of N 57 scores has a mean of m = 13. What is the value of SX for this population? b. One sample of n = 10 scores has a mean of 8 and a second sample of n = 5 scores has a mean of 2. If...

a. A population of N 57 scores has a mean of m = 13. What is the value of SX for this population?

b. One sample of n = 10 scores has a mean of 8 and a second sample of n = 5 scores has a mean of 2. If the two samples are combined, what is the mean for the combined sample?