For us, the most interesting thing happening with drones is in the super low cost category. (newscientist.com)
Instruction, instructional support, other student support, enterprise operations and food service were placed in the variable cost category. (mikekleinonline.com)
In looking over the 9 Cost Categories above, I can see that different authors will approach these tasks differently depending on the path they've chosen. (thebookdesigner.com)