Solution:

Manila --> Panama --> Havana --> Guyana -> Lusaka --> Luanda --> Uganda

Solution:

Z

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

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:

Costa

Explanation:
Costa brings the dagger made of ice in the thermos so it won't melt. He killed the Michy with the dagger and then the dagger melts with time.

Solution:

The ice just started to melt and since the sun rises from the east, Mr. Draxler is able to figure out where is north.

Solution:

The white chip is circled.

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:

288/61 hours (4 hours, 43 minutes and 17 seconds approx)

Explanation:
In 1 hour, the ratio of swimming pool filled by pipes:
1st pipe: 1/48
2nd pipe: 1/72
3rd pipe: 1/96
4th pipe: 1/6

All togther
1/48 + 1/72 + 1/96 + 1/6
=> (6+4+3+48) / 288 = 61/288.
=> 288/61 hours,

which is 4 hours 43 minutes and about 17 seconds.

Solution:

Oscaru and Austin.

Explanation:
The Chemist hide the name using periodic table as shown in below picture
76-20-44 => Os(76) + Ca(20) + Ru(44)
79-16-22-7=> Au(79) + S(16) + Ti(22) + N(7)

Solution:

When blind man "Grandpa" opened his bandages, the train must be passing through the dark tunnel. The man thought he was still blind and hence commit suicide.