At the start of a research study, a colony of penguins had a population of 20,000. One year later, it had a population of 21,200.

Assuming the population of the colony has grown exponentially, which expression best models the population? Let t represent the time in years from the start of the research study.
1,200(1.015)*
20,000(1.06)*
20,000(1.06) *t
21,200(1.012)*

The appropriate expression that best models the population is 20,000(1.06) *t.