Answer:
Back up the user data to removable disk
Explanation:
Before you work on a computer, especially anything that has to do with files not accessible, this might need to format the system because it might either be a virus or other forms of malware. Since backup was done to a different logical partition on the disk, the first thing to do before performing any diagnostic procedures on the disk is to back up the user data to a removable disk in order not to lose the information in the system.
Fist one correct.
second wrong because not all heat is used for work, some of it lost to other.
third wrong because fuel burn inside is called combustion engine
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Explanation:
i don't think rhis question could be..
Good question. When one Endorces or "Hires/ payes" someone again for a job/thing they did. I think. :)