the answer is D. all of the above
 
        
             
        
        
        
Answer:
y = 0.3X + 18.3
Step-by-step explanation:
Given that data :
x = year ;
y = trunk diameter, in inches
Year ________trunk diameter 
1 __ 18.6
3 __ 19.2
5 __ 19.8
7 __ 20.4
9 ___21.0
11 __ 21.6
13 __ 22.2
Using the linear regression calculator :
The linear equation obtained is :
y = 0.3X + 18.3
Where ;
Slope = 0.3 ; intercept, c = 18.3
 
        
             
        
        
        
I'm for sure know that it is function is linear but i would wait for others to answer also
        
                    
             
        
        
        
You can do this on a calculator if you search up online radius and height measurement calculator.
        
             
        
        
        
So, this would be a common circle question. 
First, 20 degrees from a circle's curcumference would be 20/360, which is 1/18.
This means that the length of the arc of AB should be 1/18 of the circumference.
The formula for the circumference it 2pi*r
2*pi*27=54pi
54pi* 1/18= 6 pi