There was an aeroplane crash, every single person died, but two people survived. How is this possible?

People are waiting in line to board a 100-seat aeroplane. Steve is the first person in the line. He gets on the plane but suddenly can't remember what his seat number is, so he picks a seat at random. After that, each person who gets on the plane sits in their assigned seat if it's available, otherwise, they will choose an open seat at random to sit in. The flight is full and you are last in line. What is the probability that you get to sit in your assigned seat?

Decode below three cipher riddles:

26 L of the A
7 D of the W
1000 Y in a M

Two in a corner, one in a room, zero in a house, but one in a shelter. What is it?

If you say my name, I will no longer exist. What am I?

The person who makes it has no need for it; the person who buys it has no use for it. The person who uses it can neither see nor feel it. What is it?

How many times can you subtract the number two from the number fifty?

Can you find the dog hidden in a group of pandas?

Can you count the number of lines in the below picture?

There are people and strange monkeys on this island, and you can not tell who is who (Edit: until you understand what they said - see below). They speak either only the truth or only lies.
Who are the following two guys?
A: B is a lying monkey. I am human.
B: A is telling the truth.