CC - Maths and Biology

In a biology experiment, a bacteria colony starts with 500 bacteria. Scientists observe that the number of bacteria doubles every 3 hours. The function that models the growth is: P(t)=500⋅2 t/3 where: P(t) is the number of bacteria and t is the time in h.
How many bacteria will there be after 6 hours?
What type of function is this: linear, quadratic, or exponential?
A scientist is studying the growth of bacteria in a laboratory. The number of bacteria after t hours is modeled by the function: What does the function tell us about the bacteria population after 3 hours?