Answer
Base: 3
Exponent: 4
Work Step by Step
We know that an exponential expression is in the form $a^{n}$ (where $a$ is the base and $n$ is the exponent).
Therefore, the expression $5\times3^{4}$ has a base of 3 and an exponent of 4. Since the 5 is not in parentheses with the 3, we know that the exponent is only applied to the 3.