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

By moving exactly three matchsticks can you make the below equation true.It can be solved by 3 ways.

I am under you when I am whole.
I shift above you if you remove the first letter.
I come all around you if you remove the second as well.

Can you tell me who I am?

Look at this sequence from top to bottom. What is the next number in the sequence?
1
11
21
1211
111221
312211

A wealthy man lives alone in a small cottage. Being partially handicapped he had everything delivered to his cottage. The mailman was delivering a letter one Thursday when he noticed that the front door was ajar. Through the opening he could see the man's body lying in a pool of dried blood. When a police officer arrived he surveyed the scene. On the porch were two bottles of warm milk, Monday's newspaper, a catalog, flyers, and unopened mail. The police officer suspects it was foul play. Who does he suspect and why?

Can you find the missing letter in the sequence?
S - T - I - L - ? - T - F - Y - C

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.

Find the next number in the series below

21 32 54 87 131 ?

Why is 6 afraid of 7?

I can write cow in 13 letters.

Can You?