Answer a^3-3a
a^2 times a = a^3 you add exponents
Starting from what I know (the difference between ribbons), I decided to go from the bottom and work my way up. I then noticed a pattern (each sum was three more of the previous one), and decided to keep my pattern of the three numbers but not have to do any major mental work and instead add three to the previous sum until I got to 38.
The formula for surface area of a sphere: A = 4 pi r^2.
Since the radius is 30 m then A = 4pi30^2.
30^2 x 4 =3600
A=3600pi m
The answer is B. 8/9 •4/3
Volume = length * width * height
Volume = 4.1 * 5.9 * 7.2 ≈ 4 * 6 * 7 = 168
Volume ≈ 168 in³
(C)