document.write( "Question 678353: A cylindrical tank with a diameter of 20 feet is filled with oil to a depth of 40 feet. The oil begins draining at a constant rate of 2 cubic feet per second. [Hint: depth and volume are not the same]\r
\n" ); document.write( "\n" ); document.write( "a) Write the volume of the oil remaining the tank t seconds later as a function of t.\r
\n" ); document.write( "\n" ); document.write( "b) Write the depth of the oil remaining in the tank t seconds later as a function of t.
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Algebra.Com's Answer #421355 by ankor@dixie-net.com(22740)\"\" \"About 
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A cylindrical tank with a diameter of 20 feet is filled with oil to a depth of 40 feet.
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\n" ); document.write( "Find the original volume of the oil; (radius = 10 ft)
\n" ); document.write( "V = \"pi%2A10%5E2%2A40\"
\n" ); document.write( "V = 12566.37 cu/ft of oil
\n" ); document.write( ":
\n" ); document.write( "The oil begins draining at a constant rate of 2 cubic feet per second. [Hint: depth and volume are not the same]
\n" ); document.write( "a) Write the volume of the oil remaining the tank t seconds later as a function of t.
\n" ); document.write( "V = 12566.37 - 2t
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\n" ); document.write( "b) Write the depth of the oil remaining in the tank t seconds later as a function of t.
\n" ); document.write( "Find the depth (x) of 2 cu ft in this tank, let
\n" ); document.write( "\"pi%2A10%5E2%2Ax\" = 2
\n" ); document.write( "x = \"2%2F%28%28100%2Api%29%29\"
\n" ); document.write( "x = .0063662 ft per second at a 2 cu/ft per second rate
\n" ); document.write( "d = 40 - .0063662t
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\n" ); document.write( "We can check this by finding how long it will take to empty the tank
\n" ); document.write( "12566.37/2 = 6283.2 seconds
\n" ); document.write( "Find the depth of oil drained in this time
\n" ); document.write( "6283.2 * .0063662 = 40.00 ft
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