A Population of 620 Bacteria Is Introduced into a Culture $P ( t ) = 620 \left( 1 + \frac { 4 t } { 34 + t ^ { 2 } } \right)$

Multiple Choice

A population of 620 bacteria is introduced into a culture and grows in number according to the equation $P ( t ) = 620 \left( 1 + \frac { 4 t } { 34 + t ^ { 2 } } \right)$ where $t$ is measured in hours. Find the rate at which the population is growing when $t = 2$ . Round your answer to two decimal places.

A) $226.7$ bacteria per hour
B) $68.89$ bacteria per hour
C) $65.26$ bacteria per hour
D) $51.52$ bacteria per hour
E) $61.23$ bacteria per hour