5.2.3 Can you answer these questions?

5.2.3.1 Is ClearAttributes built-in functon work in current cell only?

https://mathematica.stackexchange.com/questions/163223/is-clearattributes-built-in-functon-work-in-current-cell-only

 
I have a question. Is ClearAttributes the built-in functon work in current cell only? This is my code: 
 
In first cell: 
 
Set[a, 6] 
 
 
In second cell: 
 
ClearAttributes[Set, HoldFirst] 
Attributes[Set] 
...
 

- asked by SIJA 1vote

5.2.3.2 How to convert Piecewise into KroneckerDelta form by FullSimplify?

https://mathematica.stackexchange.com/questions/163274/how-to-convert-piecewise-into-kroneckerdelta-form-by-fullsimplify

 
The question comes from the last example of this topic in the Wolfram documentation. 
 
SeriesCoefficient[E^x^2, {x, 0, n}] 
 
 
 
 
However, my (v11.1) output is 
 
$\begin{cases} 
\frac1{{\sf  ...
                                                                                  

                                                                                  
 

- asked by ooo 1vote

5.2.3.3 Code behind these Video Playback demos?

https://mathematica.stackexchange.com/questions/163008/code-behind-these-video-playback-demos

 
There are only two known examples of video playback (from a file) within a (non-cloud) notebook: 
 
 
Visualizations in Graph Theory with the Wolfram Language (at time 3:32) 
Mathematica and CUDA,  ...
 

- asked by user5601 3votes

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