In this exercise, we will consider the problem of planning a route for a robot to take from one city to another. The basic action taken by the robot is Go (x, y), which takes it from City x to city y if there is a direct route between those cities. Direct Route (x, y) is true if and only if there is a direct route from x to y; you can assume that all such facts are already in the KB. The robot begins in Arad and must reach Bucharest.

a. Write a suitable logical description of the initial situation of the robot.

b. Write a suitable logical query whose solutions will provide possible paths to the goal.

c. Write a sentence describing the Go action.

d. Now suppose that following the direct route between two cities consumes an amount of fuel equal to the distance between the cities. The robot starts with fuel at full capacity. Augment your representation to include these considerations. Your action description should he such that the query you specified earlier will still result in feasible plans.

e. Describe the initial situation, and write a new rule or rules describing the Go action.

f. Now suppose some of the vertices are also gas stations, at which the robot can fill its tank, Extend yours representation and write all the rules needed to describe gas stations, including the Fill up action.