Which of the following situations would be modeled by an exponential growth function? 1.)the total cost of a long-distance phone call which charges $0.10 per minute

2.)the amount of a radioactive element remaining as it decreases over one year

3.)total amount of snowfall from a storm with a snowfall rate of 2 inches per hour

4.)the total amount earned after investing $1000 in a account at 5% growth each year