Y = (1.008^1/12) ^12t growth or decay

Only first two are exponential growth function and last three functions are exponential decay functions.

Step-by-step explanation:

We need to describe exponential growth or decay for the given functions.

The standard exponential function equation is

Where a is the initial value and b is the growth factor.

Note: If value of b > 1, it would be an exponential growth and if b < 1, it would be an exponential decay.

Value of b is 1.008 > 1, therefor it's an exponential growth function.

y=250 (1+0.004) ^t, also have b>1 therefor it's an exponential growth function.

All other functions has b values less than 1, therefore only first two are exponential growth function and last three functions are exponential decay functions.