What is the longest word in the dictionary?

What occurs twice in a week, once in a year but never in a day?

A pond had 60 fish, out of which, all but 20 died.
How many fishes are now present in that pond?

There is something which you can be arrested for attempting but not for successfully completing.

Find the next number in the series.
1 10 24 43 67 ?

What has six faces, but does not wear makeup, has twenty-one eyes, but cannot see? What is it?

I am a prime number.
The double of myself is equal to the square of me.

which number am I?

By using all numbers, i.e. 123456789 and subtraction/addition, operators number 100 can be formed in many ways.
Example: 98 + 7 + 6 - 5 - 4 - 3 + 2 - 1 = 100

But if we add a condition use of the number 32 is a must. Then there are limited solutions.
One of such solution is: 9 - 8 + 76 + 54 - 32 + 1 = 100

Can you tell me any other solution?

Below is the sum of symbols in each row and column in the figure. Analyzing the figure, can you find out the value of the symbols?

15 caves are arranged in a circle at the temple of doom. One of these caves has the treasure of gems and wealth. Each day the treasure keepers can move the treasure to an adjacent cave or can keep it in the same cave. Every day two treasure seekers visit the place and have enough time to enter any two caves of their choice.

How do the treasure seekers ensure that they find the treasure in the minimum number of possible days?