This is done in for parts (separated by letter)

f=H-66.4/2.26

H represents a person's height and f is the length of the person's femur bone. The equation has a margin of error of 3.42 cm.

A. Calculate the height if some of the remains. You have found several femur bones. In order to determine the heights we need to first solve the given formula H.

B. The femur bones measure 40.6 cm, 39 cm, and 48.2 cm. find the height of each person.

c. find the height of eacg person in feet.

d. using the margin of error, create an absolute value inequality to represent the range of the height for each individual.

I need help understanding both the formula for H and margin of error, please