Type I and Type II errors for a two-sided binomial test

A coin is tossed $4$ times and $p$ is the probability of getting head in a single trial. Let $S$ be the number of head(s) obtained. It is decided to test $H_0:p=\frac12$ against $H_1:p\ne\frac12$, using the decision rule: Reject $H_0$ if $S$ is $0$ or $4$. The probabilities of Type I error ($\alpha$), and Type II error ($\beta$) when $p=\frac34$, are