Do these 4 questions and SHOW ME HOW TO DO IT, please, lol. Like show the work on how you did it as well, giving brainlist to the smartest one and recommending to give a certificate to the owner if you want to go to a ivy league school this will help you get in!

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?

International calls require the use of a country code. many country codes a 3-digit numbers. country codes do not begin with a 0 or 1. there are no restrictions on the second and third digits. how many different 3-digit country codes are possible?

Sam is picking fruit from a basket that contains many different kinds of fruit. which set of events is independent?