A population has a standard deviation ? of 18.8 units. (Give your answers correct to two decimal places.) (a) What is the standard error of the mean if samples of size 11 are selected? (b) What is the...

(a) What is the standard error of the mean if samples of size 11 are selected?




(b) What is the standard error of the mean if samples of size 28 are selected?




(c) What is the standard error of the mean if samples of size 49 are selected?




(d) What is the standard error of the mean if samples of size 105 are selected?