Two dice are rolled simultaneously. The probability that the sum of the two numbers on the dice is a prime number is:

$A$ rational number is selected at random from the distinct rational numbers of the form $p/q$ formed with $p$ and $q$ belonging to the set $\{1, 2, 3, 4, 5, 6\}$. The probability that the rational number selected is a proper fraction is:

Two dice are thrown and the sum of the numbers which come up on the dice is noted. Let us consider the following events associated with this experiment:
$A:$ the sum is even.
$B:$ the sum is a multiple of $3$.
$C:$ the sum is less than $4$.
$D:$ the sum is greater than $11$.
Which pairs of these events are mutually exclusive?

For any event $A$,which of the following is true?

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

Describe the sample space for the indicated experiment: $A$ coin is tossed and a die is thrown.