Answer: 
<u>Step-by-step explanation:</u>
When you subtract b/2a from both sides, you end up with the Quadratic Formula.
Let's find the mean of all the values first.
6.3+6.4+6.5+6.6+6.8+6.8+7.5= 46.9
Let's divide by the number of values.
46.9÷7=
6.7
Now let's find the distance that each number is away from 6.7 and find the mean of those numbers.
0.4+0.3+0.2+0.1+0.1+0.1+0.8=
.2857
≈ 0.3
So, the absolute deviation is 0.3.
D I’m pretty sure. i counted all boxes and it equaled to 26
C because the formula to find the are of a circle is A=(pi) * radius^2. To find the radius from diameter, just divide by two. So 60/2= 30 so now you can just plug in and 30 * 30 is 900 and 900 * pi, or 3.1415926535, is about 2827