Q1) Based on the position of Run 1, estimate the ac eleration or gravity by fitting a polynomial in eq (14). Note that you may not have an initial speed U in a strict sense but because of accuracy in the cart's location it is advisable to fit a function as if you did have U. How you do it, it is entirely up to you. Consider using Excel, online resources (e.g. see here) or Matlab, Python, C etc. See section 4 for a short intro in Matlah