2.[10] (i) For new born babies, let y =length (height) and x =weight. For boys, the model M = B+1xi+s 1': lip-uni is suggested. A similar linear regression model holds for girls with the same slope but a different intercept as follows: yi=c+f31xi+s i=n1+1,...,n. In here '83, g and (31 are three unknown constants and ei LE N (0, 02). Write your model in the general form of a single multiple regression y = X 3 + e. by dening X and and write your M.L.E. for [fig g 51]}. Hint: In both parts (i) and (ii), the results in terms of matrices will be sufcient and you do not need to simplify