Out of four images which one is the odd one out?

Two boys wish to cross a river. The only way to get to the other side is by boat, but that boat can only take one boy at a time. The boat cannot return on its own, there are no ropes or similar tricks, yet both boys manage to cross using the boat.

How?

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?

Solve the rebus riddle in the picture below.

Find the value of "?" in the ball picture Riddle below:

Can you tell a 3D object that has just two surfaces?

How can you spell "White of an egg" in one word?
Hint: I know you can spell coke, poke, and joke.

In a university, a professor gave a set of three problems to the three brilliant students of his class. See the image for the questions.

A person was found dead on a big green land with no trees or buildings around. When the police arrived, they found a piece of rock lying next to him and the man was wearing clothes comprising of red, blue and yellow colours.

Can you tell who the person is and what was the cause of death?

Can you solve the below algebraic mathematical equation?

(J+O+I+N+T)3 = JOINT