Lisa is working on a science project to determine if commercial hair products affect hair growth speed.

It looks like you've uploaded an image containing a science project task for a student named Lisa. The task involves designing an experiment to test whether a commercial hair product affects the speed of hair growth. Let's break down the problem and solve it step by step.

---

Problem Statement:

Lisa is working on a science project. Her task is to answer the question:
"Does Product X (a commercial hair product) affect the speed of hair growth?"
Her family is willing to volunteer for the experiment.

You are asked to:

1. Describe how Lisa would perform this experiment.
2. Identify the control group, independent variable, and dependent variable.
3. Design a graph showing the results:
- Plot 2 control groups of data on a "line" (one over period of 12 weeks).
- Plot 2 experimental groups (with the product) over 12 weeks.
- Include a key (legend) for each subject.
4. Measure hair growth (independent variable) every 4 weeks for each subject.

---

Step-by-Step Solution:

#### 1. How Lisa Would Perform the Experiment

Lisa should design a controlled scientific experiment with the following steps:

- Select Participants: Use members of her family as volunteers. Divide them into two groups:
- Control Group: Does not use the hair product.
- Experimental Group: Uses the hair product regularly (e.g., daily or as directed).

- Ensure Consistency: All participants must have similar hair types, age ranges, and care routines (except for using the product), to minimize bias.

- Measure Hair Growth: Measure the length of hair at the same location (e.g., from the crown of the head) every 4 weeks for 12 weeks.

- Use Controls: Keep all other variables constant — diet, water intake, shampoo used, etc. Only the use of Product X should vary.

- Repeat Measurements: Take multiple measurements per person to reduce error.

- Record Data: Track hair length over time for each participant.

---

#### 2. Identifying Variables

| Variable Type | Description |
|--------------|-------------|
| Independent Variable | Whether or not the person uses Product X. This is what Lisa is changing. |
| Dependent Variable | The rate of hair growth (measured in cm or inches per week). This is what Lisa is measuring. |
| Control Group | The group that does not use the hair product. This group helps determine natural hair growth without the product. |

---

#### 3. Graph Design (Conceptual)

Since we can't draw the graph here, I’ll describe how to create it:

- X-axis (Horizontal): Time in weeks (0, 4, 8, 12).
- Y-axis (Vertical): Hair growth in centimeters (cm) or inches.
- Lines:
- Control Group 1: A line showing hair growth without the product.
- Control Group 2: Another control line (maybe a second person not using the product).
- Experimental Group 1: A line showing hair growth with Product X.
- Experimental Group 2: Another experimental line (second person using the product).

> Example data (hypothetical):

| Week | Control 1 (cm) | Control 2 (cm) | Exp 1 (cm) | Exp 2 (cm) |
|------|----------------|----------------|------------|------------|
| 0 | 0 | 0 | 0 | 0 |
| 4 | 1.5 | 1.6 | 2.0 | 2.1 |
| 8 | 3.0 | 3.1 | 4.5 | 4.7 |
| 12 | 4.5 | 4.6 | 6.0 | 6.2 |

- Graph Title: "Effect of Product X on Hair Growth Over 12 Weeks"
- Legend (Key):
- Blue line: Control Group 1
- Green line: Control Group 2
- Red line: Experimental Group 1
- Orange line: Experimental Group 2

> Expected Result: If Product X works, the red and orange lines will rise faster than the blue and green ones.

---

✔ Final Answer Summary:

1. Experiment Design:
Lisa should divide her family into two groups: one using the product (experimental), one not (control). Measure hair growth every 4 weeks for 12 weeks under consistent conditions.

2. Variables:
- Independent Variable: Use of Product X (yes/no)
- Dependent Variable: Hair growth rate (cm/week)
- Control Group: Family members who do not use the product

3. Graph:
- X-axis: Time (weeks)
- Y-axis: Hair growth (cm)
- Two lines for controls, two for experiments
- Key labels each group clearly

---

This setup ensures a fair test and allows Lisa to determine if the product has a real effect on hair growth.