Regular and Non-Regular Language
Think of it this way. Fix $p$ and $q$ arbitrarily – for example, take $p = 4$ and $q = 5$. Then
$$
\begin{align*}
L_1 &amp;= \{ a^4 b^{5i} : i \geq 0 \}, \\
L_2 &amp;= \{ a^4 b^5 \}.
\end{align*}
$$
Now try to answer your question. The answer will be the same no matter what values you choose for $p$ and $q$.