Consider a network of nodes a, b, c, d, e, and f. The costs of all of this network links are as following c(a, b) = 4; c(a, c) = 5; c(a, d) = 3; c(b, c) = 2; c(c, d) = 2; c(d, e) = 1; c(c, f) = 3; c(e, f) = 2 a) Draw a figure to show this network topology with the cost of the links indicated. b) Use Dijkstra shortest path computational method to determine the spanning tree from the perspective of node d in this network