My friends called me Iron59 because my parents are a chemist and a mathematician. What is my real name?

A river should be crossed by a father, a mother and their two sons and two daughters.
There are some rules that should be followed while crossing the river. There can be only two people in the raft while crossing. The daughters cannot be with their father unless there is the presence of the mother. The sons cannot be with their mothers unless the father is present. Unless the guard is on the board, the criminals cannot be with any of the family members. Only the adults like the father, the guard, and the mother knows to use the raft.

How will they cross the river?

How will you measure 15 minutes using two hourglasses of 7 minutes and 11 minutes respectively?

Which Number is the odd one out?

A) 7145
B) 2716
C) 5321
D) 4135

I am a five-letter word and people eat me. If you remove the first letter I become an energy form. If you remove the first two letters, I am needed to live. Scramble the last three letters and I am a drink. What word am I?

When can we add 2 to 11 and get 1 as the correct answer?

I know a 5-digit number having a property that With a 1 after it, it is three times as large as it would be with a one before it.

Guess the number?

what does the below rebus mean?

Can you decipher the two rows to find the hidden word?

How many words can a pen with half refill write?