Computing

You could just put each MP4 into a file and go to right click - > Properties - > Customize - > Change Icon.

Or, you can change the MP4 icon by going to:
Start -> regedit.exe -> HKEY_CURRENT_USER -> Software -> Microsoft -> Windows -> CurrentVersion -> Explorer -> FileExts -> .mp4 -> UserChoice

Then look at the value next to "Progid" and underneath "Data". For instance, mine would say gomplayer.mp4.

Then go to HKEY_CLASSES_ROOT and search for your specific file name that we just found. Once you find it, open up DefaultIcon. If there is no folder called DefaultIcon, you can right click on the folder and go to New -> Key. Name it DefaultIcon.

Once inside the DefaultIcon folder, you can then edit the value next to (Default) and underneath Data. Change the directory to your image file. For instance, if I had a folder on my desktop named MyFolder, with an image file such as MyIco.ico inside, the directory would be:

C:\Users\Taylerzy\Desktop\MyFolder\MyIco.ico, 1

The one at the end tells which icon number we are referring to (alphabetically).
http://www.tomshardware.co.uk/answers/id-1724369/change-icon-mp4-file.html

https://www.tenforums.com/network-sharing/63186-metered-wifi-bluetooth.html

Appended are a few links to 'Speed Testers'.
Speed Speed is really the quantity of designed data transfer that can be transferred over a second. It is varies widely due to type of connection and distance of travel.

Bandwidth: It is best to think of this as bandwidth, i.e. the maximum amount of data that your connection can handle without many errors. For example; when sending an email it matters little if the transfer rate is highly variable as long as the message gets sent, however stability and error free transfer is highly desirable if streaming music or video

If you do not have either Fibre to the House (FTH) or Fibre to the cabinet (FTC) then you will be connected to your local exchange by a pair of copper wires. The longer the wires the lower the signal to noise ratio etc. The built in error corrections will keep chopping the signal into small bits that can be repeated and checked and so the overall speed of data transfer will be reduced. There is a table of expected transfer rate vis a vis distance from exchange.

1. http://www.speedtest.btwholesale.com/ which has a further option to do a diagnostic test and more

2. Ookla offers it's services to third parties
http://www.supportal-test.co.uk/ a simple and quick measure of download and upload
http://www.mybroadbandspeed.co.uk/speedtester/ seems to note the provider but very quick
http://speedtest.net.uk/ simple but slow to initiate
http://beta.speedtest.net/run
https://www.ookla.com/demo?template=2&features=0 Sample of Ookla service

3. Quick download only readout: https://fast.com/

How the manual calculation of a square root works:

Take the solution algebraically as (a + b) (a + b) => a2 + 2ab + b2 => a2 + b(2a +b)

The method pairs the digits from the decimal point and starting with the most significant finds the single integer square root for that pair. The second and continuing operation adds the remainder of that to the next pair. It may be that the most significant pair is only a single digit as in one hundred and forty four 1 44

Lay out the solution as though working on long division with the object under a line and the subsequent divisors to the left below each other.

Example: Find the square root of 40.96

1. Separate the number into pairs of digits from the decimal point, which is simple in this case; rooting a number effectively halves the digits. (40 . 96)
   
   
2. Find the highest number that multiplied by itself will divide into the first 'pair' (40)
   6 x 6=36 (7 x 7=49) so we use 6 - this is 'a'
   
   
3. Place this number, as a part solution above its pair
     6
   40 . 96
   
   
4. Subtract 36 (a²) from the 40 and incorporate the next pair => 4.96
   
   

Now we use the b(2a + b) to resolve b, and can ignore the decimal point in the following processes as each solution is an integer to be placed above it's respective pair.

Now resolve the b(2a +b) from the 496

1. Double a => 12 and move one point left => 12*
2. Find a number such that 12* x * is equal to or less than 496 which in this case is 4 or b
   i.e. 124 x 4 = 496
3. Place this digit above its pair
     6 . 4
   40 . 96

With no remainder the solution is complete 6.4 is the square root of 40.96.

Should there be a remainder continue the process to find another b from the remainder and the next two digits until you find a rational solution or you have a suitably significant number.

1. Open C:/Windows/SysetmApps and find Cortana file, something like [Microsoft.Windows.Cortana_cw5n1h2txyewy]
2. Via task manger end Cortana
3. Change Cortana file name simply by adding an 'x'

To enable remove 'x' no need to end task as not running

https://superuser.com/questions/949569/can-i-completely-disable-cortana-on-windows-10