Could someone help me with this Math question ? As soon as possible ! What is the opportunity cost of buying a $.75 soda every school day for three years instead of drinking water? Assume you are in school for 36 weeks a year and that water is free.

Afarmer has a large field that is x feet in length. he wants to fence in a rectangular section in the middle of the field , leaving a length of 100 feet of open field behind each end of the fenced rectangle.he also wants the width of the fenced-in space to be 100 feet less than its length. find the expressions to represent the length and width of the fenced section of the field