Answer
See below.
Work Step by Step
The nth term of a geometric series can be obtained by the following formula: $a_n=a_1\cdot r^{n-1}$, where $a_1$ is the first term and $r$ is the common ratio.
Here the common ratio is $5$ and $a_1=3$.
Hence here: $a_n=3\cdot(5)^{n-1}$, thus $a_8=3\cdot(5)^{8-1}=234375$
