Ok so the given is the length of the diameter. diameter=28 in so the radius is half the diameter radius=28/2=14 in Circumference formula=2 × pi × radius C=2(pi)(14) - pi can be considered as 3.14 or the value in the calculator C=28(PI) C=87.96 in ≈ 88 in The easiest way is just use the diameter times the pi Because 2 times the radius is just the diameter So we can derive that C= diameter × pi C=d(pi) C=28(pi) C=87.96 in ≈ 88 in
I'm assuming you meant w^3 (w to the third power). In that case, you would just add 34 + 13 + 11 - 18 because they are all like terms (coefficients of w^3).