Find the mistake in the below maths equations

A = 2
A(A-1) = 2(A-1)
A2-A = 2A-2
A2-2A = A-2
A(A-2) = A-2
A = 1

In the figure, you can see nine stars. What you have to do is connect all of them by using just four line and without lifting your hand i.e. in a continuous flow.

Find the missing letter in the last circle logically in the given below picture.

O_er_t_o_

Complete the missing letters of the given word.

Birbal was jester, counsellor, and fool to the great Moghul emperor, Akbar.
The villagers loved to talk of Birbal's wisdom and cleverness,
and the emperor loved to try to outsmart him.
One day Akbar (emperor) drew a line across the floor.
"Birbal," he ordered, "you must make this line shorter, but you cannot erase any bit of it."
Everyone present thought the emperor had finally outsmarted Birbal.
It was clearly an impossible task.
Yet within moments the emperor and everyone else present had to agree that Birbal had made the line shorter without erasing any of it.
How could this be?

What time is it when an elephant sits on a fence?

What kind of storm is always in a rush?

What has a ring but no finger?

How can you spell "White of an egg" in one word?
Hint: I know you can spell coke, poke, and joke.

No one wants to have it, but if one got it, he does not want to lose it. What is It?