Solution:

Uncle Scrooge tells him he took the loan to keep his expensive car safe and he also saves money on security and parking rent.

Solution:

"World War I" was named after after "World War II"

Solution:

Both S and T are of same height because they are the same people.

Suppose that each person is marked with their respective number which also denotes their height.
Now when the longest from each row is called out, they will be 50, 100, 150 ... 500. Shortest among them will be 50 aka S.
When the shortest from each colum is called out, they will be 1, 2, 3, ....50. Longest among them will be 50 aka T.

Thus, they both are same person.

Solution:

The man asked the king that he wanted to die of old age.

Solution:

There is a simple logic to solve this question.
The size of the chocolate is 2 x 8. Thus, you need to have 2 x 8 = 16 pieces.
Every time you break the chocolate, you will get one extra piece.
Thus, to get 16 pieces, you must break it (16 - 1) = 15 times.

Solution:

This statement is true but only in a specific case i.e. if both of the siblings continue to live till the day the younger is as old as the elder one was during the time of their birth.

Solution:

No

Solution:

It will take the man 58 minutes to reach the top.

Since he is climbing 3 feet and falling 2 feet back every passing minute, he is actually climbing 1 feet every minute.
Therefore, he would have climbed 57 feet in 57 minutes. The remaining distance is 3 feet. He will take one more minute to climb it and reach the surface. Since he has reached the top surface, he won't slip back.

Solution:

This can be possible. They are not twins but triplets.

Solution:

He cannot marry his widow's sister in any country. This is because if his wife is a widow, he is already dead.