Abu join one of the team in e-sport competition. There are 16 teams registered and they were divided up into four room (i.e., A, B, C, D), with four teams each. Every team plays one match against the other teams in its room. After the room matches are completed, the winner from room A will play with the winner from room B, and the winner from room C will play with the winner from room D, as a semi-finals session. Then, the winners from semi-finals session will play in the final session. How many matched are played altogether? (5 marks) d) Ekhsan Sports sell nine balls. Each ball has a unique number, from 1 to 9. If six balls are chosen at random, must at least one of them be even? Why? (2 marks) e) Alisa has three different colors of ribbon (12 - Blue; 15 Yellow; 23 Pink). One day, she would like to pick some ribbons for her art class activity. If she were to pick some ribbon without looking at the color, how many must she pick to be sure of getting at least five ribbons from the same color? (3 marks)