Solution:

Bill. If you read the message upside down, you'll notice that the numbers resemble letters and that those letters form legible sentences. The message is 'Bill is boss. He sells oil.'

Solution:

You can never solve a problem on the level on which it was created.

Here is the answer key:
A-Z
B-Y
C-X
D-W
E-V
F-U
G-T
H-S
I-R
J-Q
K-P
L-O
M-N
N-M
O-L
P-K
Q-J
R-I
S-H
T-G
U-F
V-E
W-D
X-C
Y-B
Z-A

Solution:

Starting with the first two words, Take the first and last letters, reading from left to right. Example: Carrot fiascO "from these pairs" the message is as follows:

CONGRATULATIONS CODE BREAKER

Solution:

138,150,180

The series lists numbers that are flanked by two prime numbers.

4 (3 and 5 are prime)
6 (5 and 7 are prime)
12 (11 and 13 are prime)
18 (17 and 19 are prime)
30 (29 and 31 are prime)
42 (41 and 43 are prime)
60 (59 and 61 are prime)
72 (71 and 73 are prime)
102 (101 and 103 are prime)
108 (107 and 109 are prime)

thus

138 (137 and 139 are prime), 150 (149 and 151 are prime), 180 (179 and 181 are prime)

Solution:

It can be done as shown below.

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:

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:

It can be done as shown below.

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:

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

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