1. Assume you are trying to forecast US Tesla car sales by using the number of elephants in Africa as an explanatory variable.  Write a regression equation showing a zero intercept and that US Tesla sales is insensitive (unaffected by) the number of elephants in Africa. 

2. Assume you are trying to forecast US Tesla car sales by using the price of gasoline as an explanatory variable.  Write a regression equation showing a zero intercept and that US Tesla sales increase by 1,000 for every $1 increase in gasoline prices. 

3. Assume you are trying to forecast US Tesla car sales by using the price of gasoline as an explanatory variable.  Write a regression equation showing that Tesla will sell 5,000 cars regardless of the price of gasoline and that US Tesla sales will decrease by 1,000 for every $1 increase in gasoline prices. 

4. If the slope coefficient in question #2 were to halve in value what would that mean? 

5. If the intercept in question #2 was -5, what would be the interpretation for the resulting equation?