Using features on demand results in saving potentially significant amounts of disk space. features on demand becomes a third installation state per feature in windows server 2012 r2. while previous versions allowed only enable or disable, features on demand provides

The answer is Disabled with payload removed
The development is extremely crucial in the age where we contstantly receive access to overload of content.
Large hardisk means that we could store much more of the amount of data that we could put without compromising the performance.

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The steeply sloping region of a continental margin where the sea floor descends at a rate of greater than 1 ft for every 40 feet is called. continental slope.