What has lots of eyes, but can’t see?

What has a ring but no finger?

In a school, there are four subjects. Seventy percent of students study English, seventy five percent of students study Science, eighty five percent of students study Mathematics and eighty percent of students study Spanish.

Can you calculate the percentage of students that study all four subjects?

'S' refers to the number of seconds in a day and 'H' refers to the number of hours in ten years. Which quantity out of these two is greater?

Baseball bat and ball cost $100. If the bat cost $99 more than the ball, what is the cost of each?

How many letters are in the alphabet?

I have a five and a three-gallon jar. Assuming there is an infinite supply of water, how can I measure one-gallon water?

Whats the next number in the below number sequence pattern.

The following "Brain Bat" means Slow Down.
S
L
O
W

Using the same logic, can you tell us what does the following Brain Bat means ?
E
V
I
G

Nine marbles are arranged in the image below. Can you slide two marbles to form a square?