What is the word or phrase?

What can you see in the middle of March and April that you can never see in any other month?

what's the probability of getting a king or a queen from a pack of 52 cards?

'S' refers to the number of seconds in a day and 'H' refers to the number of hours in ten years. Which quantity out of these two is greater?

Decode the below four famous ciphers:

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

What is the next number in this series?

4,12,84,3612....

Find the 8 in the below-given Image.

A King wants to send the diamond ring to his girlfriend securely. He got multiple locks and their corresponding keys. His girlfriend does not have any keys to these locks and if he sends the key without a lock, the key can be copied in the way. How can King send the ring to his girlfriend securely?

Is the statement valid that it does not matter how much older a sibling is, eventually the younger one will be half as old as the older one?

Replace the question mark with the correct number.

2 + 2= 4
3 + 3= 18
4 + 4= 48
5 + 5= ?