A Scientist was fifty years old in the year 2000 but he was forty years old in the year 2010. How can this be possible?

PS: It has a logical answer.

Be active and find the killer in the picture Riddle below.

What word begins and ends with an E, but has only one letter?

Peter wakes up daily to pick up his cycle and crosses the border between Spain and France daily with a bag on his shoulder. He is investigated daily by the officials but they don't find anything suspicious.

If we tell you that he is smuggling something what would it be?

Andrew’s doctor gives him three pills and tells him to take one every half hour. How much time will have passed by the time Andrew’s taken all three pills?

The first person saw the bridge step on it and crossed,
the second person saw the bridge did not step on it but crossed,
the third person did not see the bridge did not step on it but crossed.
Who are these people?

What brings you down but never up?

I travel all around the world but always stay in the corner. What am I?

I am a seven-letter word but if you remove four of my letters I will have one left. What word am I?

Decode the below four famous ciphers:

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