What Adam and Eve do not have but the rest of the people have?

A seven-year-old kid challenged his classmates that he can make the number one disappear by adding something to it.

How can he do that?

I’m light as a feather, yet the strongest person can’t hold me for five minutes. What am I?

Pronounced as one letter,
And written with three,
Two letters there are,
And two only in me.
I am double, I am single,
I am black blue and grey,
I am read from both ends,
And the same either way.

Many have heard it, but nobody has ever seen it, and it will not speak back until spoken to. What is it?

John, a 5-year-old boy, was really fond of the chocolates. He asked his Mother to give him some money to buy his favourite chocolates. His Mother gave him $45. He went to the shopkeeper and asked, "How much is one chocolate for?". The shopkeeper said $3 for one chocolate. Also, if you give me the wrappers of three chocolates, I will give you one for the exchange.
In total, how much chocolate could John eat?

It belongs to you, but other people use it more than you do. What is it?

Can you identify the direction in which this bus is moving; left or right?

Hint: The bus is moving on the roads of London.

I have a clock(12-hour format) and both the needles of the clock overlap at 12:00.
After how much time, they will overlap again?

I make two people out of one. What am I?