At what type of recovery site would computers, devices, and connectivity necessary to rebuilt a network exist, and all are appropriately configured, updated, and connected to match your network's current state?

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.