Great and solve for the Standard deviation

The minimum value in the dataset is 2.62.
The maximum value in the dataset is 3.57.
The range is the difference between the maximum and minimum values:

$$\text{Range} = \text{Max} - \text{Min} = 3.57 - 2.62 = 0.95$$

The range is $\boxed{0.95}$.

The formula for the sample standard deviation is:

$$s = \sqrt{\frac{\sum (x_i - \bar{x})^2}{n-1}}$$

We have $n=7$ and $\bar{x} \approx 3.065714$.

First, calculate the difference between each data point and the mean $(x_i - \bar{x})$ and square it $(x_i - \bar{x})^2$:

• $2.75 - 3.065714 = -0.315714 \implies (-0.315714)^2 \approx 0.099675$
• $2.86 - 3.065714 = -0.205714 \implies (-0.205714)^2 \approx 0.042318$
• $3.57 - 3.065714 = 0.504286 \implies (0.504286)^2 \approx 0.254304$
• $2.62 - 3.065714 = -0.445714 \implies (-0.445714)^2 \approx 0.198661$
• $3.49 - 3.065714 = 0.424286 \implies (0.424286)^2 \approx 0.180018$
• $3.05 - 3.065714 = -0.015714 \implies (-0.015714)^2 \approx 0.000247$
• $3.12 - 3.065714 = 0.054286 \implies (0.054286)^2 \approx 0.002947$

Next, sum the squared differences:

$$\sum (x_i - \bar{x})^2 \approx 0.099675 + 0.042318 + 0.254304 + 0.198661 + 0.180018 + 0.000247 + 0.002947 \approx 0.77817$$

Now, substitute this sum into the standard deviation formula:

$$s = \sqrt{\frac{0.77817}{7-1}}$$ $$s = \sqrt{\frac{0.77817}{6}}$$ $$s = \sqrt{0.129695}$$ $$s \approx 0.3601319$$

Rounding to three decimal places:

$$s \approx 0.360$$

The standard deviation is $\boxed{0.360}$.