a) algorithm EdgeOnSomeShorestP ath(< u, v >, s, t) pre−cond : The < u, v > is an edge on G, s and t are vertices on G post−cond : The output is a boolean which is true when < u, v > is on some shortest path from s to t in G. begin Find the shortest path SPst from s to t using Dijkstra’s algorithm. Find the shortest path SPsu from s to u using Dijkstra’s algorithm. Find the shortest path SPvt from v to t using Dijkstra’s algorithm. If (length(SPst ) = length(SPsu ) + weight(u, v) + length(SPvt )) then return true else Find the shortest path SPsv from s to v using Dijkstra’s algorithm. Find the shortest path SPut from u to t using Dijkstra’s algorithm. If (length(SPst ) = length(SPsv ) + weight(u, v) + length(SPut )) then return true return false % return false in all other cases end algorithm