How do i close the file so i can delete it ? since it's open in another program

This os integrated the processing power of windows nt with the easy-to-use gui of windows 98. windows 2000 windows 3.11 windows for workgroups windowa millennium edition

Least square fit to polynomial write a function leastsquarefit3pol that solves a linear system of equations to find a least squares fit of a third order polynomial to an experimental data set given as two row arrays. the function leastsquarefit3pol must explicitly solve a set of linear equations and cannot use polyfit. there should be no restriction on the size of the problem that can be solved.

Hey so i was just trying out some game hacks so i took a paste from online and built it in my visual studio and then suddenly my computer was working or clicking on stuff on its own am i hacked?