What occurs twice in a week, once in a year but never in a day?

Two Twins Jack and Jill were standing back to back and suddenly they started running in opposite direction for 4 kilometres and then turn to left and run for another 3 kilometres.

what is the distance between the Baggio twins when they stop ?

To attend world science seminar, A famous chemist from Mexico visit
London. In the lab, the scientist was killed and his six assistants were under suspicion of killing the chemist.
Name of six assistants: Austin, Wayne, Dege, Oscaru, Lingard, and Rojo.
He left a note "76-20-44 79-16-22-7"

A local detective Jack was called to solve the case,

After reading the note, Jack instantly asked the police to arrest the murderers.

Who are the murderers?

As you can see that fifteen matches have been used to form an arrangement. What you have to do is remove any six of them to make them ten.

You’ll find me on Mercury, Earth, Mars, Jupiter, Saturn, and Uranus. But never Neptune, or Venus. What am I?

A man dies of old age on his 25 birthday. How is this possible?

What is the fewest number of coins that would be required in order to make sure each and every coin touches exactly three other coins?

What 5-letter word typed in all capital letters can be read the same upside down?

Jenifer is learning to drive her car. She went down a one way lane and in the wrong direction. But she do not break any law.

How come ?

Yesterday I fell from 30 feet high ladder but I don't get hurt. Why?