The temperature dropped 4 degrees each hour for 3 hours. What was the total change in temperature?

What is the answer to this problem 7 * 5/6

Ascientist has discovered an organism that produces five offspring exactly one hour after its own birth, and then goes on to live for one week without producing any additional offspring. each replicated organism also replicates at the same rate. at hour one, there is one organism. at hour two, there are five more organisms. how many total organisms are there at hour seven? 2,801 19,531 19,607 97.655

State one method by which you can recognize a perfect square trinomial.