A mile-long train is moving at sixty miles an hour when it reaches a mile-long tunnel. How long does it take the entire train to pass through the tunnel?

What happened when the wheel was invented?

Find out the missing number in the picture attached:

How many bricks does it take to complete a building that is 15 feet wide, 30 feet deep, and 12 feet tall made of brick?

I am white when I am dirty, and black when I am clean. What am I?

A train leaves from point A for point B at 80 mph. After half an hour, another train leaves from point B for point A at 60 mph.

Which of the trains will be farther from point A when they meet ?

The product of three consecutive numbers is 7980.
Then the sum of these consecutive numbers would be?

A man was going to bleach his socks because they had gotten muddy the day before. As he was pouring the bleach into the washing machine, he spilt some on the floor. He got some cleaning fluid and mopped it up with a rag. Minutes later he was dead. What killed him?

I am the first thing you need while camping.
I am always with the person named Marcos Valencia and Carrick.
But Pogba Zlatan and Rooney think I am wasteful and do not need me.
I am the second to the last thing to add when you are making a patch.

What am I?

What does this rebus puzzle means ?