Consider following table produced from Dijkstra's algorithm, fill (a) and (b) in step 1 and 2. Step 0 1 2 3 4 5 N' u ux uxy uxyv 5 2 3 127 W X Z D(v),p(v) D(w).p(w) D(x).p(x) D(y).p(y) D(z).p(z) 2,u 5,u 1,u ? 00 2,u 2,u -W- (a) 2, X (b) 3, X (a) 4, X (b) 3, Y 1 (a) 2, X (b) 4, X ?? SZ (a) 5, X (b) undefined 2 (a) (b) 3,y 2,x 00 4,y 4,y