Arthur, Who Is a Member of the Maintenance Staff of Gordon's

Arthur, who is a member of the maintenance staff of Gordon's Mall, was mending one of the revolving entry doors when he realised that he was missing an essential tool. He placed an "Out of Order" sign on the door and went to get the tool. Due to an emergency caused by a washroom flood, he was gone for longer than he expected. Not long after he left, the sign fell off the door, and, while Susan, Antoinette and Gloria were entering, the door collapsed, seriously injuring all three women. Susan was on her way to the pet store to buy cat food, Antoinette came to the mall to get decorating ideas from the paint and wallpaper shop, but was not going to buy anything, and Gloria, thinking she was dying, confessed that she was on her way to rob the jewellery store.
a. Who would Susan, Antoinette and Gloria sue and why?
b. Identify what, if any, duty of care is owed to each woman, and discuss whether any of them could win a negligence suit.