1)The Lincoln wheat penny was designed by Victor D. Brenner in 1909. Currently, the most valued penny is the 1909 S VDB penny. It was minted in San Francisco and only 484,000 were minted with the initials on the back. In 2015, the S VDB penny in uncirculated condition is worth $3,200. When will it be worth $25,000? 

2)The temperature in a hot tub is 103° and the room temperature is 75°. The water cools to 90° in 10 minutes. What is the water temperature after 20 minutes? 

After how many minutes will the temperature be 80°? 

3)The population of the United States has grown at different rates over ten-year increments as shown by the following table.

Year	Population of U.S.
1930	123.1 million
1940	132.1 million
1950	152.3 million
1960	180.7 million

If the maximum supportable population of the U.S. is 600 million people, use the logistic model to predict the population (in millions of people) of the U.S. in 2010 by using the following years as data points.

(a)using 1930 and 1940 as data points

(b)using 1950 and 1960 as data points

Compare/contrast/explain the different results.

The growth rate from part (a) is  (---Select--- equal to larger than smaller than) the growth rate from part (b).