does a deficit equal to one make in the motivation and it is still changing with the standard of hossein madahiause the educational books in the world that have been taught for years with the same textbook, and still mofaqhi ali mazaheri, i don't know which one of these currents is constantly affecting this tablet. well, this year is very important. audio books, i can't speak. we have nearly a thousand titles. this year, we have published 190 books. some of them are related to technical and professional fields . related to elementary school in our book, we consider a life span of 5 to 10 years. even the books that are used in other countries have different editions, of course , the editions are not yearly, but a period of 5 years to 6 years is considered. yes, reza, in one sense, it can be said that updating and improving the book is an essential part of the selection process. it has not happened, for example, tomorrow, saturday, after one year or two years the book needs major revision in the collection, he said that we can put it in the approved network, the main basics should not change, bec