What's the next in the series?

H, Be, F, S, Mn, Kr, In, Gd, Tl, ?

Seven Robbers robbed a bank and hide the coins in a lonely place.
They decide to divide the money equally the next morning. Two greedy robbers decided to cheat the others and reach the place at night. They equally divided the coins between them, one coin left. So they called another robber and then they decided to divide equally among the three. Sadly again one coin left. The same thing happened to the 4th 5th and the 6th robber.
However, when the 7th robber reached in the morning, they can divide the coins equally.

How many coins were there in total?

Make the seating arrangement of 10 children in such a way that there are 5 rows with 4 children in each row.

What jumps when it walks and sits when it stands?

Can you spot the hidden girl in the picture below?

If it took eight men ten hours to build a wall, how long would it take four men to build it?

One day, I thought of ways that can be used for creating a palindrome. So I decided that I will turn into a larger number by adding the reversed digits to the original number and keep doing it till I finally obtained a palindrome.

I am not sure if this process will always result in a palindrome eventually but I was able to produce a four-digit palindrome. Can you guess my starting number?

Why do you find that most of the buildings are deprived of the 13th floor?

Buy me, smell me or deliver me, I do not change.

Who am I?

Why is the Hole below a Lock?