The symmetric binomial weights for a moving average are {ak} q the 2q set of successive terms in the expansion ( 12 +2121) Write down the weights corresponding to q = 4. (b) Two linear filters are applied to the time series {xt} to produce a new series t. If the (ordered) filters are (ar) = (a_1, ao, a₁) and (bk) = (bo, b₁,b2, b3) (i) Find (c;) = (ar) ⋆ (bk), the convolution of (ar) and (bk). (ii) For (ar) = (a_1, ao, a₁) (13/3-1) and 6 (bk) = (bo, b1,b2, b3) ( 6'3'3'6 Write down linearly in terms of {xt}. . (c) Do the necessary calculations to show that V³ x is a convolution of three linear filters with weights (-1,1). =