What does below chemistry rebus means?

O_er_t_o_

Complete the missing letters of the given word.

Take 9 from 6, 10 from 9, 50 from 40, and leave 6.

How Come ??

You need to arrange three 7 and mathematical symbols to form number 1?

John Went to the nearby store in a Mall to buy something for her home. Below is the conversation between the two:

John: How much for the one?
Shopkeeper: It is $2
John: How much for the Eleven?
Shopkeeper: It is $4
John: How much for the Hundred?
Shopkeeper: It is $6.

What is John buying?

What does this rebus means ?

When monkey rotate the gear, which mark will be hit 1 or 2 ?

Can you solve the below algebraic mathematical equation?

(J+O+I+N+T)3 = JOINT

Okay before we begin with the puzzle, do keep in mind that you have to answer it quickly.

You are participating in a car race. Seeking the perfect moment, you overtake the second person in the race. What positions are you in now?

what does the below math rebus puzzle mean?