The data mule track Consider the four node sensor network as shown in Figure 12.20. Note: G is the data sink. Communication is by means of a data mule. Movement of one unit costs 3Wh.

(a) Find the optimal path for the data mule, assuming the data mule must be in close proximity to each sensor to communicate data.

(b) Now suppose that the information mule must approach within 2 units distance of the nodes A and C and 1 unit distance of the node B to attain the desired communications. Assuming negligible communications energy cost, find a circuit with near-minimum cost, and compute that cost.