Which costs remain the same in total despite changes in the level of activity? a. Variable costs b. Product costs c. Mixed costs d. Fixed costs

Fixed costs are the costs that remain constant in total regardless of changes in the level of activity. Think of them as your monthly subscription fees for Netflix or rent for your apartment—whether you binge-watch or take a month off, the payment stays the same! These costs include things like salaries, rent, and insurance. However, keep in mind that while total fixed costs remain constant, the fixed cost per unit decreases as production increases, making them an essential part of understanding business economics.