Update illustrations for x-axis date change

docs/en_us/dashboard/source/engagement/Engagement_Content.rst

@@ -42,18 +42,27 @@ tabular format and can be downloaded. See the **Content Engagement Breakdown**
 report.
 
 Examples of the Weekly Student Engagement chart follow. The first example shows
-a course that started only a few weeks ago. Callouts provide context for the
-data that is shown by indicating several recent occurrences: the beginning of
-the beta test, the course start date, and the due date of the first homework.
+a course a few weeks after the start date. The numbered callouts in the image
+provide context for the data that is shown.
 
 .. image:: ../images/engagement_chart_start.png
- :alt: A graph showing changes in number of engaged students over time.
+ :alt: A graph showing changes in the number of engaged students over time.
 
-In the second example, a small, private online course was developed on one
-instance of the platform, and then exported and imported to a different
-instance just before the course start date. The tooltip shows the number of
-students engaging in different activities on the same day that the final
-homework was due.
+#. Course development on edx.org, a period when engagement levels were low in
+   all three categories.
+
+#. The beginning of the beta test, when a slight increase in all of the
+   engagement categories can be detected.
+
+#. The course start date, when the number of active students increased
+   significantly.
+
+#. The due date of the first homework, when the number of students who tried a
+   problem increased.
+
+The second example is for a small, private online course. The tooltip shows the
+number of students engaging in different activities on the same day that the
+final homework was due.
 
 .. image:: ../images/engagement_chart_SPOC.png
  :alt: A graph with almost immediate activity in all three measures.

docs/en_us/dashboard/source/enrollment/Enrollment_Activity.rst

@@ -42,20 +42,21 @@ review in tabular format and can be downloaded.
 
 A couple of examples of this chart follow for different courses. In the first
 example, for a MOOC, you see enrollment climb fairly steadily over a period of
-several months. The markers begin with two "student" enrollments (almost
-certainly the course creator and another course team member) on the day the
+several months. The markers begin with four enrollments (almost
+certainly the course creator and other course team members) on the day the
 course was created in Studio.
 
 .. image:: ../images/enrollment_chart.png
  :alt: A chart with the periods when the rate of enrollment increased
        circled.
 
-The chart does reveal several periods when the rate of new enrollments
+The chart reveals different time periods when the rate of new enrollments
 increased rapidly, or "spiked" (circled). The team for this course might have
 the contextual knowledge to correlate those periods with marketing efforts or
 automated enrollment events, or might want to research possible explanations.
-After the final spike, which coincided with the course start date on 17
-September, enrollment continued to increase.
+After the first spike, which coincided with the course start date on 15 April,
+enrollment continued to increase and an additional spike occurred over a month
+later.
 
 The second example shows the Daily Student Enrollment chart for a small,
 private online course. In this course, the course team used the instructor

docs/en_us/dashboard/source/learners/Learner_Activity.rst

@@ -107,7 +107,7 @@ that one these activities took place. Unlike the roster, this timeline is not
 limited to activity in the last seven days.
 
 Examples of learner activity charts follow. The first example shows the
-activity chart for a learner who is playing 10 or more course videos every
+activity chart for a learner who often plays 10 or more course videos per
 day. However, the learner is not answering any problems correctly, and has not
 yet contributed to the discussions.
 
@@ -122,21 +122,22 @@ understanding of this learner's experience, you could go back to the learner
 roster and key activity report to see if this learner is attempting to answer
 problems, but not managing to answer any correctly.
 
-The next example shows the activity chart for a learner who watches one or more
-videos almost every day, and who has occasionally contributed to the
-discussions. However, there was only a single day on which this learner
-answered any problems correctly. The tooltip shows the counts for each type of
-activity on that day.
+The next example shows the activity chart for a learner who occasionally
+watches videos, and who has not yet contributed to the discussions. However,
+there were only two days on which this learner answered any problems correctly.
+The tooltip shows the counts for each type of activity on one of those days.
 
 .. image:: ../images/learner_quiz.png
  :width: 800
- :alt: A learner activity chart showing ongoing discussion and video activity,
-     and a single day with problems correct activity.
+ :alt: A learner activity chart showing relatively little video activity,
+     and just two days with problems correct activity.
 
 Knowing the context of how your course is set up, this pattern might indicate
-when the learner reached the first homework assignment. Or, it might indicate
-that the learner completed all of the ungraded practice questions and the
-midterm on one day.
+that the learner completed the first homework assignment in your self-paced
+course and then, after some weeks off, completed the second homework
+assignment. Or, it might indicate that the learner started your
+instructor-paced course on schedule, but is now rushing to complete the
+remaining graded assignments before the end of the course.
 
 Sending Email Messages to Learners
 ***********************************