My wife has this same laptop. The C-50 is not a powerful CPU. It is in the same category as the Atom, so it is not uncommon to see a lot of CPU usage doing very mundane tasks. Put this in perspective, a Core 2 Duo or Athlon X2 that came out 6 years ago is much, much faster. You can try uninstalling everything that isn't absolutely necessary and turning off Aero for a start, that might help, but I doubt there is anything seriously wrong with your system. That said, it wouldn't hurt to run a scan with Malwarebytes. Lots of malware attaches itself into explorer.exe, and can cause lots of weird issues, because making well behaved applications is not a malware writer's goal.
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