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

Solve the rebus riddle in the picture below.

You board a train. The train will have to enter a tunnel soon. You are claustrophobic. Which place is the best for you to sit?

What can go through glass without breaking it?

What is the largest amount of money that you can possess in change and still if someone asks you for a dollar, you won't be able to give?

He does not have any heart but still, He manages to live.
If you kill him, you will eventually die but yet you kill him.
He cannot run, who is He?

Can You Find The Poor LOST PUPPY Hidden In The Park in 20 Seconds?

This is a most unusual paragraph. How quickly can you find out what is so unusual about it? It looks so ordinary, you'd think nothing was wrong with it. Actually, nothing IS wrong with it. But it is not as ordinary as you might think. If you think about it for a bit, you will find out why it is truly so unusual. So what is it? What is so unordinary about this paragraph?

I am weightless, but you can see me. Put me in a bucket, and I'll make it lighter. What am I?

My thunder comes before the lightning; my lightning comes before clouds; my rain dries all the land it touches. What am I?