What file will hold the contents of RAM when the machine is powered off, and will be approximately the size of the system RAM?

The hiberfil.sys file is specifically designed to store the contents of the system's RAM when a computer enters hibernation mode. When hibernation is initiated, the operating system saves the current state of the machine, including open applications and documents, to this file on the hard drive. This file will typically be roughly the same size as the amount of physical RAM installed in the system, as it captures a snapshot of all the active memory at that moment.

In contrast, the other file types mentioned have different purposes. For example, PAGEFILE.SYS is utilized for virtual memory management by the operating system, allowing it to swap data to and from the hard drive when RAM is fully utilized, but it does not store the entire content of RAM like hibernation does. The WIN386.WFP and NTUSER.DAT files serve specific roles too; the former is related to Windows 3.x compatibility in managing memory, while the latter contains user-specific settings and preferences in the registry.