5. We want to compare two different groups of students, students taking Composition 1 in a tradition lecture format and students taking Composition 1 in a distance learning format. We know that the mean score on the research paper is 85 for both groups. What additional information would be provided by knowing the standard deviation?

By knowing the standard deviation, one gets the idea of how the value is scattered or dispersed about the mean.

Step-by-step explanation:

Let us first define standard deviation.

As it is known that the standard deviation is a measure of dispersion which express the spread of observation in terms of the average of deviations of observations from some central values.

Measure of dispersion gives us an idea about homogeneity or heterogeneity of the distribution.

Standard deviation is supposed almost an ideal measure of dispersion except the general nature of extracting the square root.  

Thus for the given question, if we want to compare the two different groups of students whose mean score is 85. Here the standard deviation for both the groups interprets an idea about how the individual score for each group scattered or varied about the mean score i.e. 85.