Can you replace the question mark with the correct number?

What type of tree can I carry in my hand?

Solve the puzzle by telling what does below picture means.

There are five men, let's say Tarun Harish Lavesh, Manoj, and Manish. All of them have a dot mark on their forehead. They can't see the dots on their forehead but can see the ones on others. The owner of WHITE Dot is an honest person and will never lie, while the owner of BLACK Dot always tells the lie.

This is the statement from Tarun Harish Lavesh and Manish:
Tarun: 'I see 3 whites and 1 black'
Harish: 'I see 4 black'
Lavesh: 'I see 3 black and 1 white'
Manish: 'I see 4 white'

What colour is the dot on each of Tarun Harish Lavesh, Manoj, and Manish's forehead?

If nine thousand, nine hundred nine dollars is written as $9,909,
how should twelve thousand, twelve hundred twelve dollars be written?

Before Mount Everest was discovered, what was the highest mountain in the world?

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?

Teacher ask the student

'Why are you standing on that chair in music class ?'.

what did student replied ?

I am the one who remains awake when you sleep. But I need to rest when you awake. Who Am I?

What is the next number in this series?

4,12,84,3612....