5. Line e and line c
6. Line a and line d
        
                    
             
        
        
        
First use Pythagoras theorem to find the remaining length of the base.
Then multiply the base with the altitude and divide that by 2 and you'll get the area
        
             
        
        
        
Circunference=diameter time pi
aprox pi to 3.14 
circunference=200.332
subsitue
200.332=diameter time s3.14
divide both sides by 3.14
63.8=diameter
answer is 63.8 units