Which of the following is true of BLUE? a. An estimator is linear if and only if it can be expressed as a linear function of the data on the dependent variable. b. It is the best linear uniform estimator. c. It is a rule that can be applied to any one value of the data to produce an estimate. d. An estimator is an unbiased estimator of if for any .

(c) the diagram shows the first three shapes of a matchsticks arrangement.first shape = 3second shape = 5third shape = 7given m represents the number of matchstick used to arrange the n'th shape.(i) write a formula to represent the relation between m and n. express m as the subjectof the formula.(ii) 19 matchsticks are used to make the p'th shape. find the value of p.