What is the below Rebus indicate?

Krish is 45 years old and his mother Crishtina is 73 years old.

Can you find out how many years ago, his mother was three times his age?

What building has the most stories?

Which word is least like the others? Third, fourth, fifth, sixth, seventh, eighth, ninth?

John drives to his office at 20km/hr. After reaching the office, he realizes that today is a holiday. He went back at an average speed of 30km/hr. Discounting the time spent in the stoppage what was the average speed of his journey?

No one wants to have it, but if one got it, he does not want to lose it. What is It?

81 x 9 = 801. What must you do to make the this equation true?

What three numbers, none of which is zero, give the same result whether they’re added or multiplied?

What does below pictogram mean?

A tree doubled in height each year until it reached its maximum height over the course of ten years. How many years did it take for the tree to reach half its maximum height?