Suppose the random variable, X, that you are studying, has a mean = m, and standard deviation (sd) = s. Then z = 1.33 is equivalent to saying that
(x - m)/s = 1.33 or that your observed value is greater than the mean by 1.33 times the sd.
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If the Z Score of a test is equal to zero then the raw score of the test is equal to the mean. Z Score = (Raw Score - Mean Score) / Standard Deviation
z-score of a value=(that value minus the mean)/(standard deviation). So if a value has a negative z-score, then it is below the mean.
Yes. If a score is below the mean, the z score will be negative.
A z score of -1.3 means that the score is located at the negative 1.3 sigma level with respect to the mean.
There is not enough information to answer your question. To determine a Z-Score, the mean and standard deviation are also required.