Over a three-year period, the value of a vintage VHS tape of “Charlene’s Greatest Hits” decreased from $\$20$ to $\$1.99$.

1. What were the annual multiplier and annual percent decrease?

   Hint (a):

   $\$20(m)(m)(m)=\$1.99$

   Answer (a):

   The multiplier is $0.463$.
   How can you use that to find the percent decrease?

2. Write the equation of the function that describes this situation.

   Hint (b):

   Use the starting value and multiplier you found in part (a) to write the equation.

   Answer (b):

   $y=20(0.463)^x$