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:

B.

In every line and column, there are bicycles where 2 of them are facing left, and 1 is facing right, 2 with 2 pedals, and 1 with 12 with a steering wheel and 1 without.

Solution:

30

Explanation:
As you can see the lower number rows are always bigger than upper row ones with the difference going up by 3 with every step

34 - 32 = 2
32 - 27 = 5 (difference going up by 3 from last difference)
56 - 48 = 8 (difference going up by 3 from last difference)
? - 19 = 11 (difference going up by 3 from last difference)
so ? = 30

Solution:

3

Explanation:
1 + 2 + 3 + 4 + 5 => 15 => 5 - 1 =>4
4 + 5 + 6 + 7 + 8 => 30 => 3 - 0 =>3
6 + 7 + 8 + 9 + 11 => 41 => 4- 1 =>3

Solution:

RS

Explanation:
The list is formed by using last two letter of planet's names in the order from Neptune To Mercury

NEPTU-NE
URAN-US
SATU-RN
JUPIT-ER
MA-RS
EAR-TH
VEN-US
MERCU-RY

Solution:

94

Explanation:
every second number is reverse of the square of a number
2 -> 4
3 -> 9
4 -> 61 (Reverse of 16)
5 -> 52 (Reverse of 25)
6 -> 63 (Reverse of 36)
7 ->94 (Reverse of 49)

Solution:

17

Explanation:
1
3 = one (3 letters)
8 = three (5 letters) + one (3 letters)
13 = Eight (5 letters) + three (5 letters) + one (3 letters)
21 = Thirteen (8 letters) + Eight (5 letters) + three (5 letters) + one (3 letters)
17 = twentyOne (9 letters) + Thirteen(8 letters)

Solution:

5 of clubs.

Explanation:
The 5th number is equal to the sum of first four number (recursively until its value <=13). The suit will be same as of biggest card.
eg Row1:
5 + 7 + 3 + 11 = 26 = 8
Since Maximum value is Jack of hearts, therefore, we will get 8 of hearts

Similarly for the last row
12+13+2+5 = 32 = 5
Since Maximum value is King of a club, therefore, we will get 5 of a club.

Solution:

Z

Explanation:
The numeric value of the first two alphabets adds up to the numeric value of the last alphabet.

Solution:

28745

Explanation

New Number = (Last Number +1 ) * 9
and Then New Number = (Last Number - 1 ) * 8 and so on.

i.e
1
(1+1) * 9 = 18
(18-1) * 8 = 136
(136+1) * 7 = 959
(959-1) * 6 = 5748
(5748+1) * 5 = 28745
(28745-1) * 4 = 114976
(114976+1) * 3 = 344931