Solution:

31

Explanation:
Ramanujan lighting the candles in binary.
11110 =30
11111 =31

Solution:

3

Explanation:
Digits are represented in binary form where a ball is 1 and a ring is 0.
001 = 1
010 = 2
100 = 4
011 = 3

Solution:

Felix

Explanation:
Iron = Fe (chemical symbol)
59 = LIX (Roman numerals)

Solution:

It can be done as shown below in the picture.

Solution:

Adam betrayed Eve.

Explanation:
Eve may not jump because of the survival instinct or can be related to some emotions and can, therefore, be given a benefit of the doubt, whereas Adam having the parachute seem a calculated plan implies that he definitely betrayed Eve.

Solution:

No

Explanation:
Assume that the rope can be stretched forever. Assume the rope is evenly stretched. The moving speed of the end point of the rope (relative to the starting point) is 1000 cm/second.

Each second the ant moves 1cm, at the same time that 1cm rope stretches to be 1000+1000t1000+1000(t−1)= t+1tcm where t is the number of seconds after the ant is on the rope. Therefore, the ant has a moving speed of t+1t cm/second.

Therefore, the moving speed of the ant is far less than the moving speed of the end point of the rope.

Filk will never reach the end of the 1000 cm long rope.

Solution:

It can be done as shown in the picture below.

Solution:

8! minutes

Explanation:
28 days x 24 hours x 60 minutes = 40,320 = 8! minutes.

Solution:

Both 3 and 4th

Explanation:
- The water in tank1 will get filled up to the connectivity of tank1 and the tank2 and then it will start flowing to tank2.
- The water in tank2 will get filled up to the connectivity of tank2 and the -tank3 and then it will start flowing to tank3.
- The water in tank3 will get filled up to the connectivity of tank2 and the tank3 and then it will start flowing to tank3.
- As the outlet of tank3 and inlet of tank4 are not at the same level, water will continue to fill tank3 till the inlet of tank4.
- Now both the tank3 and tank4 fill simultaneously until both fill together.

Solution:

111111111

Explanation:
It's a maths magical square root series as :
Square root of number 121 is 11
Square root of number 12321 is 111
Square root of number 1234321 is 1111
Square root of number 123454321 is 11111
Square root of number 12345654321 is 111111
Square root of number 1234567654321 is 1111111
Square root of number 123456787654321 is 11111111
Square root of number 12345678987654321 is 111111111 (answer)