document.write( "Question 210011: High concentrations of Carbon Monoxide (CO) can cause coma and possible death. The time required for a person to reach a COHb level capable of causing a coma can be approximated by the quadratic model. T=.0002x^2 - .316x + 127.9, where T is the exposure time in hours necessary to reach this level and 500<= x <=800 is the amount of carbon monoxide present in the air in parts per million (ppm).\r
\n" ); document.write( "\n" ); document.write( "Estimate the approximate concentration of (CO) necessary to produce a coma in 4 hrs?. \n" ); document.write( "
Algebra.Com's Answer #158722 by stanbon(75887)\"\" \"About 
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T=.0002x^2 - .316x + 127.9, where T is the exposure time in hours necessary to reach this level and 500<= x <=800 is the amount of carbon monoxide present in the air in parts per million (ppm).
\n" ); document.write( "Estimate the approximate concentration of (CO) necessary to produce a coma in
\n" ); document.write( "4 hrs
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\n" ); document.write( "4 = 0.0002x^2 - .316x + 127.9
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\n" ); document.write( "0.0002x^2 - .316x + 123.9 = 0
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\n" ); document.write( "Solve using the Quadratic Formula:
\n" ); document.write( "x = [0.316 +- sqrt(0.316^2 - 4*0.0002*123.9)]/[2(0.0002)]
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\n" ); document.write( "x = [0.316 +- sqrt(0.0007360]/0.0004
\n" ); document.write( "x = [0.316+-0.027129]/0.0004
\n" ); document.write( "x = 857.82 ppm or x = 722.18 ppm
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
\n" ); document.write( "Reply to stanbon@comcast.net
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