The population of a slow growing bacterial culture can be represented by the function P(t)=t^2-0.7t+10, where t is measured in seconds.
a) Determine the populations of bacteria at 2.5 seconds.
b) Determine the average rate of change in the bacteria population over the interval from 0 to 2.5.
c) Estimate the instantaneous rate of change in the bacteria population at exactly 2.5 seconds. (use 0.1 centered interval)