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

A King wants to send the diamond ring to his girlfriend securely. He got multiple locks and their corresponding keys. His girlfriend does not have any keys to these locks and if he sends the key without a lock, the key can be copied in the way. How can King send the ring to his girlfriend securely?

Replace the question mark with the correct number in the below-given picture?

what does this picture(rebus) riddle means ?

A bomb exploded in a room full of married couples and no one died. How?

Paul's height is six feet, he's an assistant at a butcher's shop and wears size 9 shoes. What does he weigh?

When I got four, I have it none.
When I got two, I have it some.
When I got none, I have it all.

What is it?

When you stop to look, you can always see me. But if you try to touch me, you can never feel me. Although you walk towards me, I remain the same distance from you. What am I?

What does this below rebus puzzle mean?

Which country gets ill every time?