Using the normal distribution, it is found that the z-scores are:
1) z = -0.8
2) z = 2.4
3) z = 0
In a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
Item 1:
0.8 standard deviations below the mean, hence z = -0.8.
Item 2:
2.4 standard deviations above the mean, hence z = 2.4.
Item 3:
The mean is 0 standard deviations from itself, hence z = 0.
A similar problem is given at https://brainly.com/question/24663213