A professor needs help from three student helpers to complet

A professor needs help from three student helpers to complete four tasks. The first task is grading; the second is scanning; the third is copying, and the fourth is organizing student portfolios. The estimated time for each student to do each task is given in the matrix below. Which of the following constraints represents the assignment for student A?

A. XA1 +XA2 + XA3 + XA4 1

B. XA1 +XA2 + XA3 + XA4 = 0