Medication $x ( t ) = \frac { 5000 t } { t ^ { 2 } + 13 }$

Multiple Choice

Medication. The number of milligrams x of a medication in the bloodstream t hours after a dose is taken can be modeled by $x ( t ) = \frac { 5000 t } { t ^ { 2 } + 13 }$ $t > 0$ . Find the t-value at which x is maximum. Round your answer to two decimal places.

A) 0 hours
B) 3.61 hours
C) 693.38 hours
D) 5.61 hours
E) 8.80 hours