Suppose that K = 30 for this question only. If you were to use propositional logic to represent the knowledge of the agents, which set of propositional symbols would you choose? Why? 2. What are the drawbacks and advantages to use propositional logic? 3. Suppose that K = 30 for this question only. Using the set of symbols you have chosen in question 1., express the following properties in propositional logic: (a) For every location that is a cliff, there is an adjacent location to it that contains some non null quantity of resource r1. (b) For every location that contains some non null quantity of resource r3, there is exactly one adjacent location that is a hill. (c) Resource r2 can only appear in the corners of the grid (the corners of the grid are the locations (1, 1), (30, 1), (1, 30), (30, 30)). 4. Suppose that a robot is on a grid of size 5 5 and knows the following properties: (a) for every cliff, at least one of the adjacent locations is flat and contains r2, (b) robot in (2, 2) detects a cliff in at least one of the adjacent locations, (c) there is no cliff in (1, 2) and there is no cliff in (2, 1), (d) robot in (4, 2) does not detect any cliff in any of the adjacent locations, (e) there is no resource r2 in (1, 3) and there is no resource r2 in (2, 2), (f) either there is no resource r2 in (3, 3) or there is resource r2 in (4, 3). Translate these properties into sentences of propositional logic and using the modus ponens, the resolution rule and the and-elimination, show how to deduce from these properties that there is resource r2 in (2, 4) or in (4, 3). You can reuse the set of symbols that you chose in question 1. or another one more convenient.