Problem 6 : Following sentences are given in the Knowledge Base. 1- x,y Doctor(x) villeacher(y)) v Earn More (x, y) 2- ]x Cardiologist(x)=>Doctor(x) 3- ]x Instructor(x) => Teacher(x) - Cardiologist(tom) Does Earn More (Tom, Ali)? Use Forward Chaining to prove your answer and state which inference rules you used in each step. (15 pts)