How might a psychologist study "mate selection" based on each of these four levels of psychological analysis (biological, individual, social, and cultural)?

Which of the following activities would conserve the most energy? installing a dimmer switch on a light using a blender instead of a food processor hanging clothes to dry on a clothesline instead of ironing them opening a window instead of turning on the air conditioning setting your computer's screen saver to turn on after less time has elapsed