You are trying to predict how much money you will spend on electricity if you rent an apartment with 3 other friends. What data do you need?

To predict how much money you will spend on electricity if you rent an apartment with 3 other friends, you would need the following data:

1. Average Electricity Usage: You need to know how much electricity you and your friends typically use. This can be estimated based on the number and type of electrical appliances you use, how often you use them, and their energy efficiency ratings.

2. Electricity Rates: You need to know how much your utility company charges for electricity. This is usually a rate per kilowatt-hour (kWh).

3. Seasonal Variations: Electricity usage can vary by season. For example, you might use more electricity in the summer if you use air conditioning, or in the winter if you use electric heating. So, you need to account for these variations in your estimate.

4. Shared vs. Individual Usage: You need to decide how to split the electricity bill. Will it be divided equally among all roommates, or will each person pay for their own usage? This will affect how much each person pays.

5. Length of Stay: The duration of your stay in the apartment will also affect your total electricity costs.

By gathering and analyzing this data, you can make a reasonable estimate of your future electricity costs.