What is the word or phrase?

Christina, Allison and Lena are 3 daughters of John a well-known Mathematician, When I asked John the age of their daughters. He replied "The current age of her daughters is prime. Also, the difference between their ages is also prime."

How old are the daughters?

My cousin lives in one story house in Antarctica. His house is made the of-of sandstone. what is the color of stairs?

What seven-letter word has hundreds of letters in it?

What does this rebus riddle means ?

You order chicken wings at KFC in the boxes of 6, 9 and 20. What is the largest number of wings that you cannot obtain by buying in any combination of the boxes?

I have no doors but I have keys, I have no rooms but I have space, you can enter but you can’t leave! What am I?

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

Can you find a seven digit number which describes itself. The first digit is the number of zeros in the number. The second digit is the number of ones in the number, etc. For example, in the number 21200, there are 2 zeros, 1 one, 2 twos, 0 threes and 0 fours.

Find the missing number in the image below.