Tricky Data of Bookworm's Movement

What was the data given?

Yes, bookworm only moved 10 mm distance. Read the given data given once again. 

Books are arranged in the way we normally place on the shelf. Normally, they are placed in such a way that the their spines (where most of books have name) are easily visible to us. 

If A, B and C are books having 10 pages each then with the normal placement the pages would count from 10 to 1 if counted from left to right. 

In other arrangement, they would count from 1 to 10 if counted from left to right.

See below.

Now, as per data given, the books are arranged in normal way on the shelf and the bookworm started from first page of first book to the last page of last book.
That is it must have ate only middle book which is 10 mm wide.

Hence, the bookworm must have moved only 10 mm.

The Tunnel Trouble!

A man needs to go through a train tunnel to reach the other side. He starts running through the tunnel in an effort to reach his destination as soon as possible. When he is 1/4th of the way through the tunnel, he hears the train whistle behind him. 

Assuming the tunnel is not big enough for him and the train, he has to get out of the tunnel in order to survive. We know that the following conditions are true - 

1. If he runs back, he will make it out of the tunnel by a whisker.

2. If he continues running forward, he will still make it out through the other end by a whisker.

What is the speed of the train compared to that of the man?

The train must be traveling at THIS speed!