Hey scan help me with answers to this qestion but put the answers in english

Here is the investigation design in English:

Aim
To determine the focal length and thus the power of a given corrective lens and to assess its suitability based on the ideal power range of 5.6D to 7.7D.

Variables

• Independent Variable: Object distance ($u$) from the lens (in meters).
• Dependent Variable: Image distance ($v$) from the lens (in meters).
• Controlled Variables: The specific lens used, light source, screen, and experimental environment.

Hypothesis
If the measured power of the lens ($P$) falls within the range of 5.6D and 7.7D, then the lens is suitable for its intended use.

Procedure

1. Set up an optical bench on a flat table.
2. Place a light source (such as a candle or a lamp with a cross-wire) at one end of the bench.
3. Position the corrective lens in the middle of the bench.
4. Place a screen on the other side of the lens.
5. Adjust the object distance ($u$) by moving the light source.
6. Move the screen until a sharp and clear image is formed. Measure the image distance ($v$).
7. Repeat steps 5 and 6 for at least 5 different sets of data, varying the object distance ($u$).
8. Record all data in a table.

Possible Sources of Error

• Parallax errors when reading distance measurements.
• Uncertainty in determining the sharpest image.
• The lens might not be perfectly perpendicular to the optical bench.

Precautions

• Ensure the lens is mounted vertically and centrally on the optical bench.
• Take distance measurements from the optical center of the lens.
• Use a bright light source with a distinct cross-wire to obtain a clear image.
• Avoid parallax errors by reading measurements with the eye level with the mark.

Data Presentation
The data will be presented in the following table:

Experiment	$u$ (m)	$v$ (m)	$\frac{1}{u}$ (m$^{-1}$)	$\frac{1}{v}$ (m$^{-1}$)
1
2
3
4
5

Data Analysis

1. Plot a graph of $\frac{1}{v}$ against $\frac{1}{u}$.
2. From the lens formula, $\frac{1}{f} = \frac{1}{u} + \frac{1}{v}$, we can rearrange it as $\frac{1}{v} = -\frac{1}{u} + \frac{1}{f}$.
3. The graph will be a straight line. Determine the y-intercept or x-intercept. The value of the intercept will give $\frac{1}{f}$.
4. From the value of $\frac{1}{f}$, calculate the focal length ($f$) and then the power of the lens ($P$) using the formula: $$P = \frac{1}{f}$$ Where $f$ is in meters and $P$ is in diopters (D).

Advice/Recommendation
Compare the calculated power of the lens ($P$) with the given ideal range (5.6D to 7.7D).

• If $5.6 \text{ D} \le P \le 7.7 \text{ D}$, then the lens is suitable for its intended use.
• If $P < 5.6 \text{ D}$ or $P > 7.7 \text{ D}$, then the lens is not suitable for its intended use.
• Provide advice to the learners based on these findings.