1. [10 marks] Suppose that we need to compute the matrix-chain product A1 A2 A, x A4 x As x A6. The dimensions of these matrices are given in the dimension array p as defined in class, and the content of p is 5,10,3,12,5,50,6 Final an optimal parenthesization of this matrix-chain product. You can simply write down your solution (as a fully parenthesized expression), without showing intermediate steps or arguing about correctness