4/ Find the extreme value(s) of the following function and check whether they or minima Z = f(x,y) = -x² + xy + 4x – y²2 + y %3D

Md = a1 + a2 Y + a3 R + a4 P + u (1)Ms = B1 + B2 Y + e     (2)Md= Ms = M*      (3) In this system of equations, Md represents money demand, Ms money supply, Y national income, R interest rate, and P price level. u and e are the random errors. (3) shows the equilibrium condition in money market.a) Show the endogenous and exogenous variables in this system and indicate if regressions (1) and/or (2) are identified. b) Given the system of equations, show how you estimate regression (2) using 2SLS method. Explain.

Find the inverse of the given matrix, if it exists. - 2 - 9 M = 9 40 Select the correct choice below and, if necessary, fill in the answer box to complete your choice. 40 - 9 - 1 А. М 2 -9 B. The matrix M 1 does not exist.

Realists believe that current demographic trends (uneven increases in population between richer and poorer countries) might lead states with burgeoning populations and insufficient food to seek to expand their territory or acquire food by means of war.  Group of answer choices True False