1.   Radioactivity The half-life of uranium-232 is 72 years. Find the approximate value of k in the formula y = nekt for uranium-232. Assume t is in years.
    A. 0.0012 B. -0.0024
    C. -0.0048 D. -0.0096
    Hint

  2.   Population The population of Redville grew from 5432 in 1990 to 7116 in 2000. Assuming the population is growing exponentially, predict the population of Redville in 2005.
    A. about 8360 B. about 8140
    C. about 8290 D. about 7960
    Hint

  3.   A Mickey Mantle rookie card appreciates in value 2% every year. How much was it worth in 1990 if it is worth $35,000 in 2000?
    A. $28, 712 B. $216,711
    C. $5653 D. $42,665
    Hint

  4.   A Mickey Mantle rookie card appreciates in value 2% every year. If it is worth $35,000 in 2000, when will it be worth $100,000?
    A. 2093 B. 2043
    C. 2053 D. 2065
    Hint

  5.   Two cities have insect problems. The insects in City A increase exponentially according to the equation y = 120,000e0.04t. The insects in City B increase exponentially according to the equation y = 90,000e0.08t. When will the cities have an equal amount of insects?
    A. at t = 34.66 years B. at t = 7.19 years
    C. at t = 7.89 years D. at t = 3 years
    Hint



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