2- (2 points) [OLAP Operations] Assume we have a data cube consists of three dimensions: Item, Time and Location. The values (i.e., facts) show the revenue in thousand dollars. Assume we have the following hierarchy: Page 1 of 5 Which OLAP operations should be performed in order to answer the following questions: a) [1 point] Total revenue earned by selling Mobil and Modem in Canada in Q1. b) [1 point] Total revenue earned by each item in each Quarter. 3- (1.5 points) [Predictive Analytics] The following decision tree is for the concept "buy computer" that indicates whether a customer at a company is likely to buy a computer or not. Determine if the following instances will buy a computer and explain the steps (If the tree cannot provide the value for the instance, explain why): a) [0.5 point] Alex is a young student. b) [0.5 point] Jon is middle aged with an excellent credit_rating. c) [0.5 point] David is a teenager with an excellent credit rating