What is the probability that a non-leap year has $53$ Wednesdays?

The probability of hitting a target by three marksmen are $\frac{1}{2}, \frac{1}{3}$ and $\frac{1}{4}$ respectively. The probability that one and only one of them will hit the target when they fire simultaneously,is

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

$A$ box contains $10$ good articles and $6$ with defects. One article is chosen at random. What is the probability that it is either good or has a defect?

$A$ single die is tossed. What is the probability of a $2$ turning up?

Twenty tickets are marked with the numbers $1, 2, \dots, 20$. If three tickets are drawn at random,what is the probability that those marked $7$ and $11$ are among them?