Answer:
C
Step-by-step explanation:
To solve, use inverse operations:

Now we solve for both +/- 7.
x+6=7
x=1
x+6=-7
x=-13
I think its A once again i THINK its A sorry if im wrong
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A) 8 + 7 + 5 = 20 parts
b) 220 kg ÷ 20 = 11
c) <span> 8 parts crushed gravel: 8 x 11 = 88 kg
7 parts water: 7 x 11 = 77 kg
5 parts cement: 5 x 11 = 55 kg</span>
Circumference of the cylinder = 3.14 x 3.5 = 10.99 = 11 inches
so D. 11 x 14 is correct for the first part
area of the top = PI x r^2 = 3.14 x 1.75^2 = 9.62 inches
top and bottom = 9.62 x 2 = 19.23 = A. 19 inches