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指数增长与衰减（续）
说一个函数是「指数的」，这是什么意思？
1. Trends in the behavior of exponential functions
Trends in the behavior of exponential functions
2. Summary
Summary
3. Matching shapes to rate descriptions
Which function is always increasing but increases at a decreasing rate?
4. Glacier area model
A glacier covering 142 acres shrinks 4.4% per year, so G(t) = 142(0.956)^t. What is its area 15 years later, to the nearest acre?
5. Exponential average rates on successive intervals
A decaying exponential has values 20, 5 and 1.25 at t = 2, 7 and 12. How do the average rates on [2,7] and [7,12] compare?
6. A linear model matches an exponential in the long run
A linear model fitted through two data points always predicts the same long-run behavior as an exponential model through those points.