Answer:
Use the graph to write an equation 
y = acos[b(x – h)] + k to model the situation. 
 
The amplitude is 
30 
, 
so a = 
-30 
. 
The period is 
12 
, 
so b = 
✔ pi/6 
. 
The vertical shift is k = 
50
The phase shift is h = 
-1
Choose the equation of the graph 
first option 
Explanation: