Answer:
c edge
Step-by-step explanation:
 
        
             
        
        
        
It's a value you should probably memorize:

You can derive it using some trigonometric identities, other known values of cosine, and properties of the cosine function. For example, using the double angle identity for cosine:

If  , then
, then

and you probably know that  , so
, so

When we take the square root, we should take the positive root because  whenever
 whenever  :
:

 
        
             
        
        
        
The formula is SA = bh + (s1 + s2 + s3)H
The answer is 420m^2 
I hope this helps! :)
~Ayden
 
        
             
        
        
        
Answer:
B
Step-by-step explanation:
its not A, C or D because it drops in increments of a hundred dollars every 3 years 
 
        
             
        
        
        
Answer:
X = 31
Step-by-step explanation: