Three coins are tossed once. Find the probability of getting $2$ heads.

$A$ single letter is selected at random from the word $PROBABILITY$. The probability that the selected letter is a vowel is

When two dice are thrown simultaneously,find the probability of the following:
$(1)$ The numbers are the same.
$(2)$ The difference between the numbers is $1$.

In a college, $40 \%$ of students attend the Mathematics class, $30 \%$ of students attend the Physics class, and $20 \%$ of students attend both classes. If a student is chosen at random from the college, what is the probability that the chosen student attends only one class?

The probability that a non-leap year selected at random will contain $52$ Saturdays or $53$ Sundays is

If two dice are thrown simultaneously,then the probability that $1$ comes on the first die is