Answer:
153.94
Step-by-step explanation:
A = pi * r^2
A = pi * 7^2 (radius is half of the diameter)
A = 49 * pi 
A = 153.94
i hope this helps !! 
 
        
             
        
        
        
Answer:
5
Explanation:
Let the number equal x. Half the number is then 
x
2
 and the reciprocal of that is 
2
x
The reciprocal of the number is 
1
x
 and half that is 
1
2
x
then 
2
x
+
1
2
x
=
1
2
4
x
+
x
2
x
2
=
1
2
10
x
=
2
x
2
2
x
2
−
10
x
=
0
2
x
(
x
−
5
)
=
0
Zero is not viable solution as its reciprocal is infinity. The answer is therefore 
x
=
5
 
        
             
        
        
        
Answer:9
Step-by-step explanation:
Square root of 81 is9.
 
        
                    
             
        
        
        
Answer:
3 examples of mechanical digestion:
Mastication
Swallowing
Peristalsis