What number should come in place of the question mark below?

What brings you down but never up?

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?

If 21x = 79x, what is the value of x?

It's a test that will check your IQ.

Suppose you have one 11 minute hourglass and one 13 minute hourglass.

Can you measure exactly fifteen minutes using them ?

I am green and found in the forest and have needles instead of leaves. What am I?
Hint 1: It can be used for Christmas decorations.
Hint 2: I have a strong, scent that is used in air fresheners.

If you’ve got me, you want to share me; if you share me, you haven’t kept me. What am I?

When it's bad luck to meet a black cat?

What is the last thing you take off before bed?

The more it dries, the wetter it becomes. Can you tell what it is?