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

One absent-minded ancient philosopher forgot to wind up his only clock in the house. He had no radio, TV, telephone, internet, or any other means for telling time. So he travelled on foot to his friend's place a few miles down the straight desert road. He stayed at his friend's house for the night and when he came back home, he knew how to set his clock. How did he know?

As easy as you can get into me, it is as hard to get out of me.

Do you know what I am?

What 4-letter word can be written forward, backward or upside down, and can still be read from left to right?

Decode the below four famous ciphers:

8P of the SS
1M of the E
1S of the SS
60M in 1H

An artist while painting a scenic beauty, decides to paint three layers of blue colour on the sky.

Which layer will go on the first?

What number comes next in the series?

5 15 5 18 5 24 14 20 _

John is the son of Jacob.
So,
Jacob is the_____of John's father?

What can you deduce from the following BrainBat?

CRY
LMKI

I have four wings but can't fly.
I express no emotions.
I am found on the exact spot every time you look.
I keep toiling away with a little sound.

Do you know what am I?