What has a ring but no finger?

John and Jill are madly in love with each other. To remind Jill of his pure love, John wants to send her a ring by post but in their country where burglary is quite prominent, any package that is not locked comes under the risk of being stolen for the contents.

John and Jill possess many padlocks but neither one of them has the other key.

Can you find a way John can send the ring to Jill safely?

What mathematical symbol can be put between 5 and 9, to get a number bigger than 5 and smaller than 9?

Can you decipher the below rebus?

PBLUESAISNUERSES

You have to put a letter on the following to make it a meaningful word. The only challenge is that you can't use 'E'.

S E Q U E N C _

My friends called me Iron59 because my parents are a chemist and a mathematician. What is my real name?

Nine marbles are arranged in the image below. Can you slide two marbles to form a square?

In an interview, a boy was asked an unusual question 'How two persons sitting with a table in between them can't see each other?' He was unable to reply. Can you?

A tree doubled in height each year until it reached its maximum height over the course of ten years. How many years did it take for the tree to reach half its maximum height?

It has a long neck, A name of a bird, Feeds on cargo of ships, It's not alive,

What is it?