Problem 7-07 (Algorithmic) The following questions refer to a capital budgeting problem with six projects represented by 0-1 variables x 1, x 2, x 3, x 4, x 5, and x 6: Write a constraint modeling a situation in which two of the projects 1, 3, 5 and 6 must be undertaken. For those boxes in which you must enter subtractive or negative numbers use a minus sign. (Example: -300) x1 + x3 + x5 + x6 Write a constraint modeling a situation in which, if projects 3 and 6 must be undertaken, they must be undertaken simultaneously. For those boxes in which you must enter subtractive or negative numbers use a minus sign. (Example: -300) x3 + x6 Write a constraint modeling a situation in which project 1 or 4 must be undertaken, but not both. For those boxes in which you must enter subtractive or negative numbers use a minus sign. (Example: -300) x1 + x4 Write constraints modeling a situation where project 4 cannot be undertaken unless projects 1 and 3 also are undertaken. For those boxes in which you must enter subtractive or negative numbers use a minus sign. (Example: -300) x4 x1 x4 x3 Write constraints modeling a situation where project 4 cannot be undertaken unless projects 1 and 3 also are undertaken. Assume that when projects 1 and 3 are undertaken, project 4 also must be undertaken. For those boxes in which you must enter subtractive or negative numbers use a minus sign. (Example: -300) x4 x1 x4 x3 x4 x1 + x3 +