slope=y2-y1/x2-x1 where (x1,y1) and (x2,y2) are points on the line
In this situation we know the x values of two points, and we know the slope, so we can solve for the missing y values.
slope=-7 (11,y1) (16,y2)
Now lets plug in the information into the formula.
slope=y2-y1/x2-x1 -7=y2-y1/16-11 -7=y2-y1/5 multiply both sides by 5 -35ft=y2-y1 distances cannot be negative so lets change -35ft to a positive number 35ft=y2-y1
The vertical distance between the two points is 35feet
To find the circumference of a circle you need to take the diameter times Pi. So if you need to find the diameter from the circumference, simply divide the circumference by 3.14 which is Pi
and denote the sector area as 
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(the ratio between area is the same as the ratio between coresponding angles).
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