Why is a coin placed in a bowl of water appears raised?

When a coin placed in a bowl of water and seen from above, it appears :

A coin placed at the bottom of a beaker appears to be raised by 4.0 cm. If the refractive index of water is 4/3, find the depth of the water in the beaker.

A balloon fixed to the neck of a bottle gets inflated if the bottle is placed in a bowl of hot water. Why?

A wooden block, with a coin placed on its top, floats in water as shown in figure. The distance l and h are shown here. After some time the coin falls into water. Then

A wooden block, with a coin placed on its top, floats in water as shown in figure. The distance l and h are shown here. After some time the coin falls into water. Then

Why does a coin, placed on a card, drop into the tumbler when the card is rapidly flicked with a finger?

If a marine fish is placed in a fresh water aquarium, will the fish be able to survive? Why or why not?

"A drop of oil placed on the surface of water spreads out. But a drop of water placed on oil contracts to a spherical shape". Why?

If m rupee coins and n ten paise coins are placed in a line, then the probability that the extreme coins are ten paise coins, is

Outer hard shells of two eggs are removed. One of the eggs is placed in pure water and the other is placed in saturated solution of sodium chloride. What will be observed and why?