I am the black child of a white father, a wingless bird, flying even to the clouds of heaven. I give birth to tears of mourning in pupils that meet me, even though there is no cause for grief, and at once on my birth, I am dissolved into air. What am I?

How many sides does a circle have?

In the given figure, move three matchsticks so that the resulting figure contains two rectangles.

What is in seasons, seconds, centuries and minutes but not in decades, years or days?

A mathematics teacher took exams for his students. Out of the total students, 25% passed both the tests included in the exam. However, only 42% were able to clear the first test.

Can you find out the percentage of those students who passed the first test and also passed the second test?

What is the word or phrase below?
R | E | A | D

There are three light switches outside a room. One of the switches is connected to a light bulb inside the room.
Each of the three switches can be either 'ON' or 'OFF'.

You are allowed to set each switch the way you want it and then enter the room(note: you can enter the room only once)

Your task is to then determine which switch controls the bulb?

Here is a mathematical expression that also secretly tells a movie name. What movie is that?

If your uncle’s sister is not your aunt, what relation is she to you?

What has 88 keys?