From a class of $12$ girls and $18$ boys,two students are chosen randomly. What is the probability that both of them are girls?

$A$ bag contains $13$ red,$14$ green,and $15$ black balls. The probability of getting exactly $2$ black balls when pulling out $4$ balls is ${P_1}$. Now,the number of balls of each color is doubled,and $8$ balls are pulled out. The probability of getting exactly $4$ black balls is ${P_2}$. Then:

From a pack of $52$ cards,$4$ cards are drawn. What is the probability that it has no queen?

Three coins are tossed. If at least one of them shows tail,then the probability that all three coins show tail is:

$A$ box contains $10$ identical electronic components,of which $4$ are defective. If $3$ components are selected at random from the box in succession,without replacement,what is the probability that exactly two components of the selected components are defective?

$2$ dice are thrown. Find the probability of getting a sum greater than $10$.