What has lots of eyes, but can’t see?

You have a three-gallon and a five-gallon measuring device. You wish to measure out four gallons.

Two friends decide to get together; so they start riding bikes towards each other. They plan to meet halfway. Each is riding at 6 MPH. They live 36 miles apart. One of them has a pet carrier pigeon and it starts flying the instant the friends start traveling. The pigeon flies back and forth at 18 MPH between the 2 friends until the friends meet.

How many miles does the pigeon travel?

If,

20 % 5 = 24

21 % 7 = 33

42 % 6 = 67

Then;

66 % 6 = ?

Aman has 1.15 rupees in his pocket. There are a total of 6 coins in his pocket.

When his friend asked him for a change, he could not give change for a rupee and five paisa.

Can you tell which coins he has?

What mathematical symbol can be put between 5 and 9, to get a number bigger than 5 and smaller than 9?

When Jack was six years old he hammered a nail into his favourite tree to mark his height. Ten years later at age sixteen, Jack returned to see how much higher the nail was. If the tree grew by five centimetres each year, how much higher would the nail be?

A man is lying dead in a field where no one is around. His head is split open and his legs are disfigured. Near to him, there is an unopened package. No living organism can be found anywhere at the crime scene.

How did he die?

I am not a bull but I have horns.
I am not an ass but I have a pack saddle.
Wherever I go, I leave silver behind me.

Who am I?

Eight of us go fourth, not back, to protect our king from an attack. What are we?