Part II Short Essay Question 3: Collaborative filtering is one data mining technique that is popularly used by manyl websites (e.g., Amazon, Netflix) to make personalized recommendations. One challenge faced by collaborative filtering is making recommendations on newly registered users (the \"cold start\" problem). 1) What is user-based collaborative filtering? Describe the procedure of making prediction using this technique (no need to write down any formula). 2) Why is the recommendation new users difficult? 3) What solutions can you propose to address the cold start problem? Please give TWO solutions