what does the below math rebus puzzle mean?

John, Jack and Jill are in a desert. John doesn't like Jill and hence decides to murder him. He poisons the water supply of Jill. Since it is a desert area, Jill must drink or he will die of thirst.

Jack does not know of the actions of John and also decides to murder Jill. To succeed in his ill motives, he removes the water supply of Jill so he dies of thirst.

Jill dies due to thirst. Who murdered Jill?

What will be the best approach to finding all the prime numbers less than 75 that leave an odd reminder when we divide them with 5?

What is the coolest letter in the alphabet?

If I remove one from eleven it becomes Ten and if I remove one from nine also becomes Ten. How?

Which statement is true out of the following?
One statement here is false.
Two statements here are false.
Three statements here are false.

What is the largest number you can write with just 3 digits?

Which letter of the alphabet has the most water?

There are forty elephants and they have forty-fore heads. How can this be possible?

A man is shown a portrait painting. He looks closely, then tells, “Brothers and sisters have I none, but that man’s father is my father’s son!” Who is the man in the portrait?