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

What does this rebus riddle means ?

Known by all without exception, Forever here, for your protection, Sometimes strong, sometimes weak, Right after the night I come - hot and chic. And while millions of miles away, I always get to you, I find my way. No life around could do without me, Can you guess what I might be?

Pronounced as 1 letter, And written with 3, 2 letters there are, and 2 only in me. I’m double, I’m single, I’m black blue and grey, I’m read from both ends, and the same either way. What am I?

There is a place where if I stand up straight, I will still be considered sideways.

Can you find out the missing number in the grid?

Can you divide the below-given shape into four equal and identical pieces?

What is the difference between a jeweller and a jailer?

I welcome the day with a show of light, I stealthily came here in the night. I bathe the earthy stuff at dawn, But by noon, alas! I'm gone.

By what process could you make a 'Tea-Table' into food?