Question: Suppose if Xab = the production of item a in period b, then to indicate that the limit on production of the Corporation's "3" products in period 2 is 400,
a. X32 400
b. X21 + X22 + X23 400
c. X12 + X22 + X32 400
d. X12 + X22 + X32 400
e. X23 400