Read the passage below and answer the questions based on the understanding of the passage 

A book is written, not to multiply the voice merely, not to carry it merely but to perpetuate it. The author has something to say which he perceives to be true or useful or helpfully beautiful. So far he knows no one has said it, so far as he knows no one else can say it. He is bound to say it clearly and melodiously if he may; clearly at all events. In the sum of his life, he finds this to be the thing or group of things, manifest him; this, the piece of true knowledge, which his share of sunshine and earth has permitted him to seize. That is a book.