Yоu аre аnаlyzing different time series prоblems. Fоr each scenario, select the most appropriate model. Scenario 1 You are modeling a city's daily energy system using three related time series: electricity demand, natural gas usage, and solar power generation. You believe these three variables affect one another over time. You also want to include external variables such as temperature, humidity, and holiday indicators. Scenario 2 You are studying the interaction between inflation, unemployment, and interest rates, where all variables influence each other over time. Scenario 3 You are modeling a single company’s stock return using its past returns and an external market index (e.g., S&P 500), but you are not modeling the market index itself.