What does the following BrainBat signifies?

ABCDEFGHIJKLMNOPQRSTUVWYZ

QQQQQQQQQQQQQQQQQQQQQQQQQ.

I am a seven-letter word but if you remove four of my letters I will have one left. What word am I?

I’m light as a feather, yet the strongest person can’t hold me for five minutes. What am I?

I came first on earth but second on the heaven.
I also came twice in a week but found just once in a year.
I stay away from months but you can find me in February.

What am I?

I am beautiful, up in the sky. I am magical, yet I cannot fly. To people I bring luck, and to some people, riches. The boy at my end does whatever he wishes. What am I?

If I remove one from eleven it becomes Ten and if I remove one from nine also becomes Ten. How?

Lifeless eyes on my smiling face and watch your child's sleeping place. In their dreams they hold me tight. What am I?

How can you write nineteen in a manner that if we take out one, it becomes twenty?

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?

If six children and two dogs were under an umbrella, how come none of them got wet?