Exhibit 13-1
an Express Delivery Service Company Recently Conducted a Study

question 22

Essay

Exhibit 13-1
An express delivery service company recently conducted a study to investigate the relationship between the cost of shipping a package (Y), the package weight in pounds (X₁), and the distance shipped in miles (X₂). Twenty packages were randomly selected from among the large number received for shipment, and a detailed analysis of the shipping cost was conducted for each package. The sample information is shown in the table below:
$$\begin{array} { c c c } \text { Cost of Shipment } & \text { Package Weight } & \text { Distance Shi } \\\$ 3.40 & 4.3 & 100 \\\$ 2.10 & 0.5 & 165 \\\$ 11.10 & 5.3 & 245 \\\$ 2.70 & 6.1 & 52 \\\$ 2.00 & 4.7 & 58 \\\$ 8.10 & 3.7 & 255 \\\$ 15.60 & 7.2 & 265 \\\$ 5.10 & 2.6 & 214 \\\$ 1.10 & 0.8 & 105 \\\$ 4.50 & 0.95 & 285 \\\$ 6.10 & 6.4 & 120 \\\$ 1.80 & 1.3 & 95 \\\$ 14.60 & 6.7 & 245 \\\$ 14.10 & 7.7 & 195 \\\$ 9.30 & 6.8 & 165 \\\$ 1.20 & 2.9 & 50 \\\$ 12.20 & 8.3 & 165 \\\$ 1.60 & 0.9 & 85 \\\$ 8.10 & 4.6 & 207 \\\$ 4.00 & 3.4 & 150\end{array}$$
-Refer to Exhibit 13-1.Add the second explanatory variable (distance shipped)to the regression model.Estimate and interpret the slopes of this expanded model.

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Definitions:

Environmental Problems

Issues caused by human activities or natural processes that damage the natural environment or negatively affect people's health and quality of life.

Eutrophic Lakes

Bodies of water that are rich in nutrients like nitrogen and phosphorus, leading to excessive growth of algae and a decrease in oxygen levels.

Clear Water Species

Refers to aquatic organisms that thrive in clean, unpolluted water environments, indicating healthy aquatic ecosystems.

Water Pollution

The contamination of water bodies, like lakes, rivers, oceans, and groundwater, caused by pollutants being discharged directly or indirectly into water sources.