Question 4: NP-Hardness - Set Packing Problem (15 pts) The Set Packing Problem is stated as follows: Given a set Uof n elements, a collection Si, S2, ..., Sm of subsets of u, and a number k, does there exist a collection of at least k of these subsets with the property that no two of them intersect? Show that Set Packing is NP-hard. Hint: which well-known NP-hard problem can be reduced to this