A pond has a minnow population of 20,000 that is increasing at a rate of 5% per year. The minnows' algae food supply is decreasing so that it supports 750 less minnows each year. How is the population of minnows growing, and how is the supply of algae declining?

Both the minnows' population growth and the algae supply's decline are linear.
Both the minnows' population growth and the algae supply's decline are exponential.
The minnow population is growing exponentially and the algae supply is declining linearly.
The minnow population is increasing linearly and the algae supply is declining exponentially.