Suppose that we have a sample space $S=\left\{E_1, E_2, E_3, E_4, E_5, E_6, E_7\right\}$, where $E_1, E_2, \ldots, E_7$ denote the sample points. The following probability assignments apply: $P\left(E_1\right)=.05, P\left(E_2\right)=20, P\left(E_3\right)=.20, P\left(E_4\right)=.25, P\left(E_5\right)=.15, P\left(E_6\right)=.10$, and $P\left(E_7\right)=05$. Let
$$
\begin{aligned}
& A=\left\{E_1, E_4, E_6\right\} \\
& B=\left\{E_2, E_4, E_7\right\} \\
& C=\left\{E_2, E_3, E_5, E_1\right\}
\end{aligned}
$$
a. Find $P(A), P(B)$, and $P(C)$.
b. Find $A \cup B$ and $P(A \cup B)$.
c. Find $A \cap B$ and $P(A \cap B)$.
d. Are events $A$ and $C$ mutually exclusive?
c. Find $B^c$ and $P\left(B^{\circ}\right)$.