The answer is c i’m pretty sure
Use the equation 2πr (so it would be 2π5 or 31.4)
Answer:
y ≤ -1/5x +1
Step-by-step explanation:
The line had an incline of -1/5 and the intersect with the y-axis is 1, so the line is given by
y = -1/5x +1
The indicated area in graph is below the line, so now you have enough to get the right inequality:
y ≤ -1/5x +1
Given that mean of quiz scores = 6.4 and standard deviation = 0.7
And we need to use Chebyshev's theorem to find the range in which 88.9% of data will reside.
Chebyshev's theorem states that "Specifically, no more than
of the distribution's values can be more than k standard deviations away from the mean".
That is 


k = 3
So, we want the range of values within 3 standard deviations of mean.
Hence range is [mean -3*standard deviation, mean +3*standard deviation]
= [6.4 - 3*0.7 , 6.4+3*0.7]
= [6.4 - 2.1 , 6.4+2.1] = [4.3,8.5]