Can you find out the missing number in the grid?

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

I look at you, you look at me, I raise my right, you raise your left. What am I?

O_er_t_o_

Complete the missing letters of the given word.

Imagine you are in a room with no windows or doors. How will you get out?

A car is crossing a 20 km-long bridge. The bridge can support at most 1500kg of weight over it. If somehow, the weight on the bridge becomes more than that, it will break.

Now, the weight of the car is exactly 1500kg. At the midway, a bird comes and sits on the roof of the car. This bird weighs exactly 200 grams.
Can you tell if the bridge breaks at this point or not?

Move three sticks of the spiral below to form a square.

Manish has to secure 40% marks to pass his B.tech final exams.
He got just 40 marks and failed by 40-marks.

What is the maximum marks?

I cry without having a voice.
I fly without having wings.
I bite without having teeth.
I whisper without a mouth.

Who am I?

What is common among 11, 69, and 88?