What is the difference between an activity inventory and an object inventory?

Write a method so that the main() code below can be replaced by the simpler code that calls method original main(): public class calcmiles { public static void main(string [] args) { double milesperhour; double minutestraveled; double hourstraveled; double milestraveled; milesprhour = scnr. nextdouble(); minutestraveled = scnr. nextdouble(); hourstraveled = minutestraveled / 60.0; milestraveled = hourstraveled * milesperhour; system. out. println("miles: " + milestraveled); } }