Answer:
I am not certain if its right 
Step-by-step explanation:
 
        
             
        
        
        
The factorial ! just means we multiply by every natural number less that the value so
6! =6×5×4×3×2×1= 720
for permutations we use the formula n!/(n-r)!
so we have 8!/(8-5)!=8!/3!=8×7×6×5×4
for combinations s we have n!/(n-r)!r!
so we have 12!/(12-4)!4!=12!/8!4!=12×11×10×9/4×3×2=11×10×9/2=99×5 
        
             
        
        
        
It's the third one and the last one are the only ones that make immediate sense.
        
                    
             
        
        
        
Step-by-step explanation:
area of missed triangle =1/2×2×4=4 cm2 
area of whole rectangle =4×8=32 cm2 
area of shape =32_4 =28cm2