Prof. Lee is trying to decide what items (listed in the table below) to purchase for all the MBA students, under a budget of $20k. As an expert in Management Science, Prof. Lee wants to build an IP model to solve this problem, using the five binary decision varaibles (A, B, C, D, E) shown in the first column below. For example, if iPads are purchased for all MBA students, A = 1 and otherwise A = 0.

Decision variable	Item	Cost	Relationship with other decision variables
A	iPads	$750/student	If this is purchased, must also buy iPad cover
B	iPad covers with MBA logo	$25/student	This is not needed unless we buy iPads
C	Speaker series (Inviting 5 popular industry speakers)	$15,000	Can't afford both this and iPads
D	Wall Street Journal (WSJ) subscriptions	$10/student	Don't need if we have its electronic version
E	Electronic version of WSJsubscriptions	$5/student	Don't buy it (as it's worthless) if we don't buy iPads

Sub-question 1: What describes the relationship between the purchasing decisions for iPads and iPad covers with MBA logo? ____ ABCD____

A) B - A 0

B) B - A = 0

C) B + A = 1

D) B + A 1

Sub-question 2: What describes the relationship between the purchasing decisions for iPads and Speaker series? ____ ABCD____

A) A - C 1

B) A + C 1

C) A - C = 0

D) A + C = 2

Sub-question 3: What describes the relationship between the purchasing decisions for WSJ subscription and its electronic version subscription? ____ ABCD____

A) E + D = 0

B) E + D = 1

C) E + D 2

D) E + D 1

Sub-question 4: Wat describes the relationship between the purchasing decisions for electronic WSJsubscription and iPads? ____ ABCD____

A) E - A = 0

B) E - A = 1

C) E - A 0

D) E - A 1

Sub-question 5: What represents the budget constraint? Assume that there are 20 MBA students. ____ ABCD____

A) 750A + 25B + 15,000C + 10D + 5E 20,000

B) 20A + 20B + C + 20D + 20E 20,000

C) A + B + C + D + E 20

D) 15,000A + 500B + 15,000C + 200D + 100E 20,000

Sub-question 6: What represents that at least three items must be purchased for all MBA students? ____ ABCD____

A) 20A + 20B + C + 20D + 20E 3

B) 20A + 20B + C + 20D + 20E 3

C) A + B + C + D + E 3

D) A + B + C + D + E 3