Let's break down the problem.

• The window is 7 feet wide by 12 feet high.
• The total area that needs to be covered by the curtains would be the area of the window.

Step 1: Calculate the Area of the Window

The area $A$ of a rectangular window is given by:

$A = \text{width} \times \text{height} = 7 \, \text{feet} \times 12 \, \text{feet} = 84 \, \text{square feet}$

Step 2: Determine the Appropriate Model

The calculation involves area, which is a 2-dimensional measurement (length × width). This means the relationship between the dimensions and the area is a quadratic relationship, because it's based on multiplying two lengths (which forms a second-degree polynomial).

Correct Answer:

• The appropriate model is quadratic, and the total amount of fabric needed is 84 square feet.

Let me know if you'd like more details, or have any questions!

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Here are 5 related questions to expand on this topic:

1. How do you determine whether a model is linear or quadratic?
2. What is the difference between square feet and cubic feet?
3. How would the fabric amount change if the seamstress doubled the height of the window?
4. What would be the total amount of fabric needed if the width and height were both increased by 2 feet?
5. How can you derive a formula for the area of different shapes like triangles or circles?

Tip: For problems involving area, always check if the measurements involve length and width, as this typically means a quadratic relationship.