Two SHIPS leave port at the same time. One charts a course towards the Horsehead Nebula at 15 light-years per hour and the other charts a course for the Eagle Nebula at 20 light-years per hour. Find a function that models the distance D between the ships in terms of the time T (in hours) elapsed since their departure.

Speaking of time and travel, here is a gone but not forgotten SHIP by valgarise called “THE SOURCE OF LIFE” from 2012.

And since we’ve already got the way-back machine spun up, why not stay in 2012 and take another look at the mighty SHIP “Silenus” by Jean-Philippe Lajoie Dorval (zwitl).