Which expression represents the area of the shaded rectangle?

Lisa has three classes that each last 50 minutes. what is the total number of minutes of the three classes

Can someone me with the property questions for 12 13 and 14 plz

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