How is exponential growth and decay used in everyday life?

Suppose the radius of a circle is 16. what issuppose the radius of a circle is 16. what is its circumference its circumference

The train station clock runs too fast and gains 5 minutes every 10 days. how many minutes and seconds will it have gained at the end of 9 days?

Name each raycalculation tip: in ray "ab", a is the endpoint of the ray.