Supposed you plan to take a simple random sampling of size n from a population that has a mean 80 and standard deviation 20. If you were to double the sample size to 2n, the standard deviation of the...

Supposed you plan to take a simple random sampling of size n from a population that has a mean 80 and standard deviation 20. If you were to double the sample size to 2n, the standard deviation of the sample mean would be multipled by

a. 1/√2n

b. 1/√2