A rare live recording album of the rock group "The Beagles'appreciates in value such that its value doubles every 6 years. The album was originally purchased on January 1,1978 at

a price of $4.25. (a) State an equation that models the value of the album over time after the original purchase. Define the variables that you use. (b) What is the value of the album on January 1, 2021? (c) Approximately in how many years will this album reach a value of $20 000, assuming that it continues to increase in value according to the same equation?