The concentration of a drug $t$ seconds after injection is given by $$C(t) = \frac{3 t + 1}{7 t^2+2 } .$$ Graph this function on your calculator.

Estimate the time at which the concentration is highest (your answer needs to be correct to at least one place past the decimal point):

Maximum is at $t =$

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If this function has a horizontal asymptote, give its $y$-value. If there is no horizontal asymptote, type in none .

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What does a horizontal asymptote mean in the context of this problem? An explanation will be provided when you get the answers above correct.