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1. Page 156 ½ pt for each column

2. ½ pt for each 24 • Express the number of bacteria after 80 minute periods using exponents. __________ • Express the number of bacteria after 120 minute periods using exponents. __________ • Express the number of bacteria after 240 minute periods using exponents. __________ • Express the number of bacteria after 300 minute periods using exponents. __________ • Bacteria is said to reproduce “exponentially.” What might this mean? 26 212 215 Every time the bacteria reproduce, the number doubles.

3. Title – 1 pt • X axis (time) – ½ pt • Y axis (# bacteria) – ½ pt

4. Appears “steady” from 0 – 160, but population is doubling. 160-220 min 220 – 300 min • Is the graph steady? If so, from when to when? • From what point(s) in time do you notice the graph increasing slightly? • From what point(s) in time do you notice the graph begin to increase sharply? • Based on this information, when is the rate of bacterial growth fastest? • At 225 minutes, how many bacteria were on the kitchen counter? • At 250 minutes, how many bacteria were on the kitchen counter? • Explain what process you used to figure out your answers to questions 8 and 9. • If you had 15,000 bacteria on the kitchen counter, for how many minutes were the bacteria dividing on the counter? Rate = # bacteria/time ; Fastest towards the end, although it doubles every time. About 3,000 About 6,000 Interpolating – We used the graph to estimate a value Between two known values. About 275 min