Didn't understand C3_W3 Quiz question

How do I calculate this? and why are there no single normal distribution in the options, like why are there “=” signs in options?

Sample mean = (-1+0+1+2)/4 = 0.5
Sample variance = ((-1-0.5)^2+(0-0.5)^2+(1-0.5)^2+(2-0.5)^2))/4 = 1.25
Therefore, N(0.5, 1.25) looks like the correct option, but what does the right hand side “N(0.5, 1.12^2)” represent? Am I missing something?

The standard deviation (\sigma) is the square root of the variance:

\sigma = \sqrt{1.25} \approx 1.12

So, \text{N}(0.5, 1.25) is the same as \text{N}(0.5, 1.12^2) .


Thank you.