Question: Use the data found in spreadsheet called problem #4 to estimate

\(MC{{F}_{t}}={{\beta }_{0}}+{{\beta }_{1}}*Tem{{p}_{t}}+{{\beta }_{2}}*Weeken{{d}_{t}}+{{\beta }_{3}}*customer{{s}_{t}}+{{\beta }_{4}}*(Tem{{p}_{t}}*customer{{s}_{t}})+\varepsilon \)

Customers is the number of individual homes in the system. The new variable \((Tem{{p}_{t}}*customer{{s}_{t}})\) is called a “cross-product term.” We did not study it in class. However, if you truly understand how to answer question 3, you will be able to estimate this equation AND answer the following questions.

a. What is the marginal impact (onto MCF) if customers increase to 76,000 from 75,000, if it is a weekend and the temperature is 50F⁰? Does this marginal impact make sense to you? Please explain in a two or three sentences.

b. What is the marginal impact (onto MCF) if temperature goes DOWN from 50F0 to 49F0 when it is a weekend and there are 75,000 customers? Does this marginal impact make sense to you? Please explain in two or three sentences.