It is always ahead of me yet I can never see it. What is it?

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

Can you solve the below tricky visual equation?

There are 2 sand hourglasses.

The small one can measure 5 hours and the large one can measure 7 hours.

How can we measure 16 hours with 2 sand hourglasses running together ?

Can you name some countries which do not have the alphabet 'A' in them?

What does below science rebus mean?

Ag Ag Ag
Ag SPOON Ag
Ag Ag Ag

There's one "sport" in which neither the spectators nor the participants know the score or the leader until the contest ends.

What is it?

I am the first thing you need while camping.
I am always with the person named Marcos Valencia and Carrick.
But Pogba Zlatan and Rooney think I am wasteful and do not need me.
I am the second to the last thing to add when you are making a patch.

What am I?

Can you find the key in the picture below?

If nine thousand, nine hundred nine dollars is written as $9,909,
how should twelve thousand, twelve hundred twelve dollars be written?