Which transformation will map an isosceles trapezoid onto itself?

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?

Given sin28.4=.4756, cos28.4=.8796, and tan28.4=.5407 find the cot of 61.6

Harry is at the depot in dover and has deliveries to make in edinburgh, glasgow and aberdeen. from dover which of the deliveries is the shortest distance?