C, encoding difficulties as he struggles to store the information within the brain and recall for the short or long term
GIS (global informational system)
GPS (global positioning system)
VGA (Video graphic array)
Remote Sensing (The scanning of earth by satellite to obtain information about it)
So now that we have the definitions down, GIS,GPS,VGA, and Remote sensing provide a better understanding of what is happening at a local or global level by explaining the steps being taking to obtain the information. GIS gathers the information of the region, GPS creates the route of the region, VGA connects the information and routes gathered by GIS and GPS to your cellular device, and Remote sensing may seem like the same concept of GIS however remote sensing uses satellite images of a wider area.
Sorry if this explanation seems long, or seems to not make sense. I'm just learning about this stuff and thought I'd try to answer (:
Answer:
All of the above.
Explanation:
An audio-visual element is an electronic media that comprises of both sound (audio) and video (visual) used for teaching or a presentation.
The movement and audio-visual elements of these type of visual aid that capture audience attention are film, videotape, and multimedia.
Being that audio-visual possess both sound and visual components, they're able to foster and enhance deeper knowledge or understanding about a particular subject being played.
Multimedia such as films, videotape, mobile phones, computers, television etc are all audio-visual elements that has a robust graphical user interface and as such it focuses on improving on the cognitive abilities of it's audience or learner.
An audio-visual element basically captures the attention of the audience and keeps them glued, motivated and eager to learn more, as they can both see and hear the information being passed at the same time.

1) x=9, because we can use the Pythagorean theorem, x^2 + 144 = 225, x^2 = 81
2)
, because 6^2 +6^2 = 72, 
3)
, because 
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