Answer:
d. 
Step-by-step explanation:

 
        
             
        
        
        
Answer:
symmetric property 
Step-by-step explanation:
with symmetric property if x=y then both values on either side of the equal sign will be equal
 
        
             
        
        
        
Answer:
Part 1) 
Part 2) 
Step-by-step explanation:
Part 1) what is the measure of angle AFE
we know that
The measure of the interior angle is the semisum of the arches that comprise it and its opposite.
<u>Note:</u> In this problem the correct measure of arc EA is 40 degrees (see the picture)
so

substitute the given values

Part 2) what is the measure of angle  EFB?
we know that
 ---> by supplementary angles (form a linear pair)
so 
substitute the given value

