What is in seasons, seconds, centuries and minutes but not in decades, years or days?

An express train takes 3 seconds to enter the tunnel which is 1 km long.
If it is travelling at 120 km an hour, how long will it take to pass completely through the tunnel?

Identify the 10 differences between the two given pictures.

I went to the bookshop and spent one-half of the money that was in my purse.

When I came out, I found that I had as many cents as I had dollars and half as many dollars as I had cents when I went in. Find the money in my purse when I entered the store.

I am under you when I am whole.
I shift above you if you remove the first letter.
I come all around you if you remove the second as well.

Can you tell me who I am?

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

Why is it very easy to weigh a fish?

There is a number which when you multiply by 3 and subtract 2 from the result, then the resulting number is the reverse of the actual number.

What is the smallest number that stands true on the statement?

Can you solve the maths in the below-given picture equation?

Our product and our sum always give the same answer. Who are we?