In a concert, Christina is performing a dance show with her group.
At 10:00, she and her crew were dancing in an absolutely straight line. At that time Christina was standing in 4th position from both the front and back end of the row.

What was the size of her crew?

Can you decipher these quotes by Albert Einstein?
Blf xzm mvevi hloev z kilyovn lm gsv ovevo lm dsrxs rg dzh xivzgvw.

You Throw The Outside, Cook The Inside
Eat The Outside, Throw The Inside.

What Is It?

Can you find the missing piece of the Porsche?

There is a square of a particular number which when doubled, becomes 7 more than its quarter.

Can you find the number?

When Jack was six years old he hammered a nail into his favourite tree to mark his height. Ten years later at age sixteen, Jack returned to see how much higher the nail was. If the tree grew by five centimetres each year, how much higher would the nail be?

A 52% bias toss for head using the 51% tail bias coin was done to obtain a fair result.

Can you find how bias is the floor in this case?

I am the beginning of everything, the end of everywhere. I'm the beginning of eternity, the end of time and space. What am I?

As easy as you can get into me, it is as hard to get out of me.

Do you know what I am?

Can you tell a 3D object that has just two surfaces?