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2 years ago

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The volume of a sphere is 972π cubic millimeters. What is the circumference of the great circle of the sphere? (Recall that the

formula for the volume for a sphere is v=4/3π^3 and the formula for the circumference of the great circle is C=2πr.)
A. 9π mm
B. 18π mm
C. 36π mm
D. 162π mm

2 answers:

Mashcka [7]2 years ago

8 0

$\boxed{\boxed{\text {Volume =} \dfrac{4}{3} \pi r^3}}$

Given that the volume is 972π mm³, find radius:

$972\pi = \dfrac{4}{3} \pi r^3$

$r^3 = 972\pi \div \dfrac{4}{3} \pi$

$r^3 = 729$

$r = \sqrt[3]{729}$

$r = 9 \text{ mm}$

Find Circumference:

$\boxed { \boxed {\text{Circumference = }2 \pi r}}$

$\text{Circumference = }2 \pi (9)$

$\text{Circumference = }18 \pi \text{ mm}$

Lelu [443]2 years ago

7 0

Answer:

18

Step-by-step explanation:

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Substitute into the ODE:

$(9at^3+(9b-18a)t^2+(9c-12b+6a)t+2b-6c)e^{-3t}+3(-3at^3+(3a-3b)t^2+(2b-3c)t+c)e^{-3t}=t^2e^{-3t}$

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