Why Wine Glass Stem is so long?

When can we add 2 to 11 and get 1 as the correct answer?

It's a protector.
It sits on a bridge.
One individual can see directly through it, while others wonder what it hides.

What is it?

I cannot talk, but I always reply when spoken to. What am I?

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

Who am I?

A bank customer had $100 in his account. He then made 6 withdrawals. He kept a record of these withdrawals, and the balance remaining in the account, as follows:

Withdrawals Balance left
$50 $50
$25 $25
$10 $15
$8 $7
$5 $2
$2 $0
----- -----
$100 $99

Why are the Totals not tallying?

Two-person want to cross a river. Only one boat is present on the riverside that can carry only one person at a time.

However, they still manage to cross the river. How is it possible?

If it took eight men ten hours to build a wall, how long would it take four men to build it?

Find the smallest sentence with all the English alphabet.

The horse jumps over the king.
Strangely there is absolutely no scratch on him.

Can anyone explain, how is this possible?