Answer:
Step-by-step explanation:
let X1,X2 represents the length of two pieces selected from a population
the mean and standaerd deviation for the length of these two pieces X1,X2 is 30 cm and 0.14 cm
let X2,X3 represents the length of two pieces selected from a population
the mean and standaerd deviation for the length of these two pieces X2,X3 is 45 cm and 0.31 cm
To be continued on the attachment: