The event $A$ is independent of itself if and only if $P(A) = $

Describe the sample space for the indicated experiment: $A$ coin is tossed four times.

Two integers are chosen at random and multiplied. The probability that the product is an even integer is

Let the sum of two positive integers be $24$. If the probability,that their product is not less than $\frac{3}{4}$ times their greatest positive product,is $\frac{m}{n}$,where $\operatorname{gcd}(m, n)=1$,then $n-m$ equals :

The probability of getting at least one tail in $4$ throws of a coin is

Two dice are thrown. If the first die shows $5$,what is the probability that the sum of the numbers on both dice is $8$ or more than $8$?