What is the main component of the EV3 Lego Robot called?

Design a pos circuit that displays the letters a through j on a seven-segment indicator. the circuit has four inputs w, x, y, and z which represent the last 4 bits of the uppercase ascii code for the letter to be displayed. thus, if wxyz = 0001 then "a" will be displayed. (any answer with 22 or fewer gates and inverters, not counting any for the inputs, is acceptable)

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); } }

List a few alternative options and input and output over the standerd keyboard and monitor. explain their functioning in details.