There are $5$ red,$3$ white and $2$ yellow roses in a vase. One rose is selected at random from the vase. Then,the probability that the selected rose is yellow is ..........

$A$ class consists of $35$ boys and $25$ girls. One student is selected at random to be the class monitor. Find the probability that the selected student is a girl. (in $/12$)

When a balanced die is rolled,the probability of getting a number greater than $4$ on it is ..........

Chits numbered from $1$ to $100$ are put in a box and a chit is drawn randomly from the box. The probability that the chit drawn bears a $2$-digit number is ............

$A$ carton of $24$ bulbs contains $6$ defective bulbs. One bulb is drawn at random. What is the probability that the bulb is not defective? If the bulb selected is defective and it is not replaced, and a second bulb is selected at random from the rest, what is the probability that the second bulb is defective?

Two unbiased dice are thrown once. Write all the possible outcomes of this experiment. What is the probability that the sum of numbers on two dice is a prime number?