This question: 4 point(s) possible Submit test A certain experiment produces the data (1, 1.8), (2, 2.8), (3, 3.3), (4, 3.8), and (5, 4.1). Describe the model that produces a least-squares fit of these points by a function of the form y = B1x + 2x2. Such a function might arise, for example, as the revenue from the sale of x units of a product, when the amount offered for sale affects the price set for the product. B1 a. Give the design matrix and observation vector for the unknown parameter vector B = B 2 b. Find the associated least-squares curve for the data. a. The design matrix is X =. The observation vector is y = _. b. The least-squares curve for the data is given by the function y = x + () x2. (Round to two decimal places as needed.)