Hi there!
There are many ways to find the measure of an exterior angle of a triangle. I'll explain the easiest method to you. As you can see in the image, a line is drawn extending a side of the triangle. In order to find the measure of the exterior angle, we can subtract the measure of the 
adjacent interior angle from 180 (a straight angle). Doing this subtraction will give us the measure of the exterior angle.
Hope this helps!! :)
 
        
        
        
Option C:
Area of the wall  square feet
 square feet
Solution:
Length of the wall =  feet
 feet
Width of the wall =  feet
 feet
Area of the wall = length × width
                            
  
Convert mixed fraction into improper fraction.
                           
                           
                           
Convert improper fraction into mixed fraction.
                           
Area of the wall  square feet
 square feet
Option C is the correct answer.
 
        
             
        
        
        
136 should be your answer
        
             
        
        
        
A=7,500×(1+0.06÷4)^(4×2)
A=8,448.69
Interest earned=8,448.69−7,500
Interest earned=948.69
        
                    
             
        
        
        
10 to the 2nd power only means 10x10=100
35.6/100=0.256
35.6/10x10=0.256