Answer:
Figures A,D are polygons. 
Reason:
Polygon is a closed figure with atleast three strange lines and angles. 
 
        
             
        
        
        
Answer:
Angle 2 is 40 degrees and angle 11 is 50 degrees
Step-by-step explanation:
 
        
             
        
        
        
12/8=3/2 TIMES THE OPPOSITE <span />
        
                    
             
        
        
        
(Mass) 2160g (Divided by) / (Volume) 240cm (Equals) = 9 (Density)