After a special medicine is introduced into a petri dish full of bacteria, the number of bacteria remaining in the dish decreases rapidly. The relationship between the elapsed time ttt, in seconds, and the number of bacteria, B(t)B(t)B, left parenthesis, t, right parenthesis, in the petri dish is modeled by the following function:
B(t)=8500⋅(827)t3
Complete the following sentence about the rate of change of the number of bacteria.
Round your answer to two decimal places.