What does below chemistry rebus means?

I am 5 letters long.
My first two tell you who I am
My first 3 could be a medicine
My last three reversed could be a young boy.
My 4th, 3rd and 2nd in that order could be a fruit drink.
If you have me you may hang me round your neck
WHAT AM I ?

A father's child, a mother's child, yet no one's son.

Who am I?

In a school, there are four subjects. Seventy percent of students study English, seventy five percent of students study Science, eighty five percent of students study Mathematics and eighty percent of students study Spanish.

Can you calculate the percentage of students that study all four subjects?

You are given a cube that is made with the help of 10x10x10 smaller cubes summing up to a total of 1000 smaller cubes. You are asked to take off one layer of the cubes.
How many remain now?

What does this rebus means ?

PROG WORKRESS

Who can jump higher than a Mountain?

If eleven plus two equals one, what does nine plus five equal?

Can you think of any three-dimensional shape that comprises of exactly two surfaces?

Can you find the next number in the below sequence
3 , 7 , 10 , 11 , 12 , 17 ?