How to replace 30 laptops (and $10,000) with 150 sheets of paper
The professor for my software engineering course in college posed a problem with a non-tech answer similarly.You have a cabin in the woods, with electricity and a freezer.  You go hunting and bag a deer with much more meat than can be used in one visit, so you freeze it for use on a future visit.  But you want to know while you are away if the electricity fails for any length of time so that the meat may have thawed and spoiled.After the class spent most of a period arguing over remote monitoring systems and temperature sensors and the like, the professor revealed the simple answer.  Freeze a block of ice in the freezer and mark its height.  If it is shorter when you return, the power was out so some of it melted.