Final answer:
The y-intercept of the function represents the number of frogs in the pond at the beginning, or at year 0.
Step-by-step explanation:
The y-intercept of a function represents the value of the dependent variable when the independent variable is zero. In this case, the function is f(t) = 5(4)^t, which represents the number of frogs in a pond after t years. The y-intercept occurs when t = 0, so we can substitute t = 0 into the function to find the value at the y-intercept:
f(0) = 5(4)^0 = 5(1) = 5
Therefore, the meaning of the y-intercept is that there are 5 frogs in the pond at the beginning, or at year 0.