Can you find out the remainder when 3^300 is divided by 5?

What is the next number in this matchsticks series riddle?

In this image, you can see three almost identical Doraemon images. Can you spot the odd one out from them?

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

Two fathers and two sons decided to go to a shop and buy some sweets upon reaching. Each of them bought 1 kg of sweet. All of them returned home after some time and found out that they had 3kg of sweets with them.

They did not eat the sweets in the way, nor threw or lose anything. Then, how can this be possible?

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

A game is being played where eight players can last for thirty-five minutes. Six substitutes alternate with each player in this game. Thus, all players are on the pitch for the same amount of time including the substitutes.

For how long is each player on the pitch?

In 1990, a person is 15 years old. In 1995, that same person is 10 years old. How can this be?

Two guards were on duty outside a barracks. One faced up the road to watch for anyone approaching from the North. The other looked down the road to see if anyone approached from the South. Suddenly one of them said to the other, "Why are you smiling?"

How did he know his companion was smiling?

I have no doors but I have keys, I have no rooms but I have space, you can enter but you can’t leave! What am I?