Is this to question number 3 correct?

The head librarian at the library of congress has asked her assistant for an interval estimate of the mean number of books checked out each day. the assistant provides the following interval estimate: from 740 to 920 books per day. what is an efficient, unbiased point estimate of the number of books checked out each day at the library of congress?

One of the inventors of integrated circuits observed that the number of transistors that fit on an integrated circuit will double every 24 months. what type of relationship most appropriately models this situation?

How to use order of operation in 20 divide by 4 multiply 5 = 1