Solution:

The sun is a star.

Explanation:
Let us find out how we got there.

- Substitute a word with its antonym.
The pound is not a start.

- Eliminate one letter from one word.
The pound is not a star.

- Remove one word.
The pound is a star.

- Take out a letter and insert another in its place.
The sound is a star.

- Take out two letters from one word.
The sun is a star.

Solution:

"x", sides reversed, is "x".

It can be infinitely extended as
"x", sides reversed, is "x", sides reversed, is "x", sides reversed, is "x".

Solution:

What is your color

Explanation:

== Step-1 : Write all the colors ==
White White Black White Blue
Silver Pink Blue Blue Blue
Orange Purple Purple Gray Blue
Orange Orange Yellow Black Yellow

== Step-2: select nth letter of, where n is the column number (Note: we will ignore blue ==
w h a t _
s i _ _ _
o u r y _
o r l c o

== Step-3 : Unscramble each row==
what
is
your
color

Solution:

It can be done as shown below.

Solution:

There are multiple solutions to the brain teaser.

1) 11+13+3! = 30
2) 11.5+5.5+13 = 30
3) 11+13+6(rotating 9)... my favorite.

Solution:

Felice & Nicolas.

The number corresponding to the atomic number of the elements.
26-3-58 (FE-li-ce) =>Felice
28-27-57-16(Ni-co-la-s) => Nicolas.

Also explained in the video.

Solution:

It can be done as shown below.

Solution:

Nothing good on television

Solution:

100

list of consecutive numbers that does not contain a 'T' in the spelling

Solution:

twice of ten is twenty too :p