A random survey of enrollment at 2020community colleges across the United States yielded the following figures:

21,851; 2,149; 9,414; 7,681; 3,200; 17,500; 9,200; 7,380; 18,314; 6,557; 13,713; 17,768; 7,493; 2,771; 2,861; 1,263; 7,285; 28,165; 5,080; 11,649.

(a) Assume the underlying population is normal.

i. x=

i. sx=

iii. n=

iv. n1=