please show the solution of ques 4, 5, 6 step by step

QUESTION 4 [Quiz] (Make or Buy) Let M be the number of units to make and B be the number of units to buy. It costs $2 to make a unit and $3 to buy a unit, and the total number of units for sale must be at least 4000. Formulate an LP to minimize the total cost. [Quiz] (Make or Buy) The objective is ___ A. max M+B B. min 2M + 3B OC.min M+B D. max 2M + 3B QUESTION 5 [Quiz] (Make or Buy) Let M be the number of units to make and B be the number of units to buy. It costs $2 to make a unit and $3 to buy a unit, and the total number of units for sale must be at least 4000. Formulate an LP to minimize the total cost. [Quiz] (Make or Buy) The constraint is A. 2M + 3B 4000 C.M+B 4000 QUESTION 6 [Quiz] (Make or Buy) Let M be the number of units to make and B be the number of units to buy. It costs $2 to make a unit and $3 to buy a unit, and the total number of units for sale must be at least 4000. Formulate an LP to minimize the total cost. (Hint: Draw the feasible region and find the extreme points.) [Quiz] (Make or Buy) The optimal objective value is A. Z* = 8000 B.Z. - 16000 OC.Z* = 4000 OD.Z* = 12000