Mario is giving an informative presentation about methods for analyzing big datasets. He starts with the very basics, like what a big dataset is and why researchers would want to analyze them. The problem is that his audience consists primarily of researchers who have worked with big data before, so this information isn’t useful to them. Which key issue mentioned in the textbook did Mario fail to consider?

Audience knowledge level

Explanation:

The Key issue that Mario failed to consider when preparing for her presentation is known as Audience knowledge level.  

Because Audience knowledge level comprises educating your audience with extensive information about the topic been presented. she actually tried in doing this but she was educating/presenting to the wrong audience ( People who are more knowledgeable than her on the topic ). she should have considered presenting a topic slightly different in order to motivate the audience.

answer would be

assuming you are in the home page.

1) go to the upper right hand corner

2) click on your "profile picture"

3) go down to "edit profile"

4) it should be titled as "edit your profile", click on "profile picture"

5) choose a file

6) press "change"

you're profile picture is updated

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