Step-by-step explanation:
4 is the A or Ampltiude
To find the period set it equal to 2 pi/B


b=

b=

There is no phase shift
The midline or d or vertical shift is 1.
Our equation for 8 is

9.Use sin function. The a value is 2 or -2 your choice.
Set up the period equal to the equation



Which equal 6.
B=6
There is no C and the D and Vertical Shift is 1.
Our equation is

Hello
the answer is 14.56
Have a nice day
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$20-$14.56=$5.44
The mechanic would get $5.44 back as change.