Jim is a building contractor.Bob is a builder who works for Jim under a contract of service.Bob is currently engaged in the building works of a multi-storey building, which Jim undertook to erect.Dave is a truck-driver who agreed to provide services to Jim for this particular construction work.Although it is Jim’s responsibility to instructDave as to what work needs to be done,Dave is responsible for providing his own machinery and his own assistants.(a) WhileBob was working on the multi-storey building, the scaffolding on which he was standing collapsed andBob fell on the grounD、Bob was not wearing the protective helmet, which had been provided by Jim to all the builders.Bob suffered a serious head injury.(b) WhileDave was working at the building site, he negligently left one of his trucks switched on and unattendeD、The truck rolled away from the building site and smashed intoAlice’s house, which was right across the street.Alice’s house suffered extensive damage.Required:Advise Jim as to his legal liability in respect of (a) and (b) above. (10 marks)