Why were the advancements of the Ancient Chinese important to Visual Communication and Visual Representation?

Which of these is most responsible for differences between the twentieth century to the twenty-first century?

The graph shows median weekly earnings for full-time workers according to education level. which can you not conclude?

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.