Answer/Explanation:
Mary's careful planning influence the outcome of the story by coldly and carefully plans a way in which she will not be accused of the crime. This influences the outcome of the story, ensuring that Mary is not blamed for the murder. For Instance, Mary goes out after the murder and talks to the grocer for a while. This allows Mary to have an explanation in case she is considered a suspect. Another example is the way in which Mary cooks the lamb leg that she used to kill her husband. This allows her to hide the weapon, as well as to further develop her image as a perfect wife. Also told the police to eat the lamb leg so Mary's can get rid of the murder weapon.