Suppose xt = m + wt + qwt1, where wt ? wn(0, s2w ). (a) Show that mean function is E(xt) = m. (b) Show that the autocovariance function of xt is given by gx(0) = s2w (1 + q2), gx(?1) = s2w q, and gx(h) = 0 otherwise.(c) Show that xt is stationary for all values of q 2 R.(d) Use (2.20) to calculate var( ¯ x) for estimating m when (i) q = 1, (ii) q = 0, and (iii) q = 1 (e) In time series, the sample size n is typically large, so that (n1) n ?1. With this as a consideration, comment on the results of part (d); in particular, how does the accuracy in the estimate of the mean m change for the three different cases?

Someone answer this asap rn for ! a discount store’s prices are 25% lower than department store prices. the function c(x) = 0.75x can be used to determine the cost c, in dollars, of an item, where x is the department store price, in dollars. if the item has not sold in one month, the discount store takes an additional 20% off the discounted price and an additional $5 off the total purchase. the function d(y) = 0.80y - 5 can be used to find d, the cost, in dollars, of an item that has not been sold for a month, where y is the discount store price, in dollars. create a function d(c(x)) that represents the final price of an item when a costumer buys an item that has been in the discount store for a month. d(c(x)) =

Jimmy can run 3.5 miles in 20 minutes. how far can ne run in one hour and ten minutes?

Isaac wants the equation below to have no solution when the missing number is placed in the box. which number should he place in the box?