Final answer:
Without additional context, it is difficult to ascertain the specific cost in Maisie's relationship with Laura; however, emotional toll could be a likely factor. A similar situation is described with Mary experiencing role conflict as she manages multiple responsibilities.
Step-by-step explanation:
The cost of Maisie's relationship with Laura could encompass various factors such as emotional toll, financial burden, time commitment, or social isolation. However, without more context, it is challenging to determine which specific cost applies to their relationship. Looking at the information provided, individuals may assess their relationships like naive economists, weighing the costs and benefits. In the scenario presented, an emotional toll could be a plausible cost if the relationship brings more stress than joy. On the other hand, the case of Mary showcases an example of role conflict, as she juggles multiple roles that could potentially clash as she takes on additional responsibilities.