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Please help me work through this thank you! read the question carefully since it can be confusing

Please help me work through this thank you! read the question carefully since it can-example-1
User Ric Tokyo
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1 Answer

19 votes
19 votes

ANSWER

636,255 cubic centimeters

Step-by-step explanation

Given:

Thickness = 0.02 cm

Diameter = 45m = 4500cm

Recall, Volume of a sphere is:


V=(4)/(3)\pi r^3

Determine change in V by differentiating the Volume:


\begin{gathered} \Delta V=dV=3*(4)/(3)\pi r^(3-1)dr \\ dV=4\pi r^2dr \end{gathered}

Note: from the given question

dr = 0.02cm

r = 4500/2 = 2250 cm

Recall: for Hemisphere


\begin{gathered} dV=(1)/(2)*4\pi r^2dr \\ dV=2\pi r^2dr \end{gathered}

Substitute the values:


\begin{gathered} dV=2*3.142*(2250)^2*0.02 \\ dV=6.284*5062500*0.02 \\ dV=636255cm^3 \end{gathered}

Hence, the amount of paint needed is 636,255 cubic centimeters.

User Marc Esher
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3.2k points