What does does this rebus picture means ?

What can you see in the middle of March and April that you can never see in any other month?

What is both possible and impossible at the same time?

I want to fill my bucket using both cold and hot water.
I have two taps for both cold and hot water. The hot water tap fills the bucket in exact 6 hours and the cold water tap fills the bucket in exact 4 hours.
I turn both of them simultaneously but I forgot to turn off another tap which removes the water out of the bucket. This tap can empty the bucket in 12 hours.

How Long will it take to fill the bucket?

With the help clues provided in the image, can you find the 5 digit key?

There was once a college that offered a class on probability applied to the real world. The class was relatively easy, but there was a catch. There were no homework assignments or tests, but there was a final exam that would have only one question on it. When everyone received the test paper it was a blank sheet of paper with a solitary question on it: 'What is the risk?'.Most students were able to pass, but only one student received 100% for the class! Even stranger was that he only wrote down one word!
What did he write?

Which tank will fill first?

What is the centre of gravity?

When it's bad luck to meet a black cat?

A clock loses 10 minutes each hour. If the clock is set correctly at noon, what time is it when it reads 3 PM?