Can you arrange four 9's and use at most 2 math symbols, to make the total 100?

Two-person want to cross a river. Only one boat is present on the riverside that can carry only one person at a time.

However, they still manage to cross the river. How is it possible?

There are people and strange monkeys on this island, and you can not tell who is who (Edit: until you understand what they said - see below). They speak either only the truth or only lies.
Who are the following two guys?
A: B is a lying monkey. I am human.
B: A is telling the truth.

Count the Triangle in the figure given below:

Optical Illusion: People with hawk eyes can spot a different car in 5 seconds. Can you? Test your vision now!

This is a simple one. You just have to count the number of Fs in the given sentence.

Finished Files are the result of years of scientific study combined with the experience of years.

How many did you count?

Katniss and Peeta are liars. They both lie on some specific days.

Katniss lies on Fridays, Saturdays and Sundays. She speaks the truth on all other days.

Peeta lies on Tuesdays, Wednesdays and Thursdays. He speaks the truth on all other days.

Can you tell that one day of the week when both of them will say "Tomorrow, I will lie."?

Can you name an animal whose killing cannot be performed without spilling your own blood?

Two in a corner, one in a room, zero in a house, but one in a shelter. What am I?

Can you solve below mathematical equation?

2^1234 - 2^1233