##Copy and paste the following code to R

mao=c( 6.8, 8.4, 8.7,11.9,14.2,18.8,
       9.9, 4.1, 9.7,12.7, 5.2, 7.8,
       7.8, 7.4, 7.3,10.6,14.5,10.7)