A study found a linear correlation between the number of household appliances and the monthly electricity usage. The relationship is modeled by the regression equation $\hat{y}=50.8+12.4x$, where $x$ represents the number of household appliances, and $\hat{y}$ represents the predicted monthly electricity usage in kilowatt-hours ($\text{kWh}$). What is the predicted electricity usage for a home with $9$ appliances?

• A. $148.9\text{ kWh}$
• B. $161.0\text{ kWh}$
• C. $162.4\text{ kWh}$
• D. $159.5\text{ kWh}$

Answer: (C)