Fingers.

Nothing.

There are no stairs it is a 1 story house!

Charcoal.

C. Steel.

Sound can travel in air at approximately 332 metres per second. Sound waves travel faster and more effectively in liquids than in air and travel even more effectively in solids. Sounds can travel at approximately 6000 metres per second in some solids and at a quarter of this speed in water.

I am a shadow.

A monkey!

At 120 km/h, it took the racecar driver 1 minute to cover the first 2 km. To reach an average speed of 240 km/h for 4 km, that distance must be travelled in 1 minute. However, that time was already used up in the first half of the course. Therefore, the answer is that, no matter how fast the racecar drives in the second part of the course, it is impossible to average 240 km/h for the entire course!

You passed with flying "collars"

The night.

A book. Authors can speak to you through a book, yet the book makes no sound. Books are sold and have many duplicate copies. A book can bring the reader to tears and laughter, they span the globe and the leaves of a book (a single sheet in a book is called a leaf) can get you wrapped up in the story that you’re unaware of what’s going on around you.

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