$A$ card is selected from a pack of $52$ cards. Calculate the probability that the card is an ace.

For two events $A$ and $B$,if $P(A \cup B) = \frac{3}{4}$,$P(A \cap B) = \frac{1}{4}$,and $P(A') = \frac{2}{3}$,then find $P(A' \cap B)$.

An event $A$ is independent of itself if $P(A) = \dots$

The vertices of a regular tetrahedron are marked $1, 2, 3, 4$. If three such tetrahedra are thrown simultaneously,what is the probability that the sum of the numbers on the faces is $5$?

Let $A$, $B$, and $C$ be three events such that $P(A \cap \bar{B} \cap \bar{C}) = 0.6$, $P(A) = 0.8$, and $P(\bar{A} \cap B \cap C) = 0.1$. Then, the value of $P(\text{at least two among } A, B, \text{ and } C)$ equals:

Let $S$ be the sample space of the random experiment of throwing simultaneously two unbiased dice with six faces (numbered $1$ to $6$) and let $E_k = \{(a, b) \in S : ab = k\}$ for $k \geq 1$. If $p_k = P(E_k)$ for $k \geq 1$,then which of the following is correct?