What is always in front of you but can’t be seen?

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

What runs around the whole yard without moving?

How can you make the following equation true by drawing only one straight line: 5+5+5=550 ?

If you drop me I’m sure to crack, but give me a smile and I’ll always smile back. What am I?

What 8 letter word can have a letter taken away and it still makes a word. Take another letter away and it still makes a word. Keep on doing that until you have one letter left. What is the word?

Replace the question mark with the correct number in the below-given picture?

One absent-minded ancient philosopher forgot to wind up his only clock in the house. He had no radio, TV, telephone, internet, or any other means for telling time. So he travelled on foot to his friend's place a few miles down the straight desert road. He stayed at his friend's house for the night and when he came back home, he knew how to set his clock. How did he know?

2, 3, 5, 9, 17, _ What is the next number in the sequence?

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?