owing, where x is in hours. 3. 2. 1- --2- (Note that the graph passes through integer coordinate points.) stimate the average value of the rate over the interval x = -1 to x = 3. erage value = 3/4 (thousands of algae/hr) J stimate the total change in the population over the interval x = -3 to x = 3. tal change = -1 (thousands of algae).

The number of bacteria in a culture increases rapidly. The table below gives the number N (t) of bacteria at a few times t (in hours) after the moment when N = 1000. Time t (hours) 0 3.1 6.2 12.4 15.5 Number of bacteria N(t) 1000 1589 2612 4100 6425 (a) Find the average rate of change for the number of bacteria from 0 hours to 3.1 hours. bacteria per hour (b) Find the average rate of change for the number of bacteria from 6.2 hours to 15.5 hours. bacteria per hour S