The Texas Consolidated Electronics Company is considering an R&D program encompassing eight research projects. In the model for this problem Xi is a 0-1 variable for the selection of project i, where i = 1 to 8. One of the conditions in the model for this problem is that either project 2 or project 5 must be selected but not both of them. This condition is represented by the following constraint:Group of answer choices𝑥2+𝑥5=1

The constraint 𝑥2+𝑥5=1 in the model represents the condition that either project 2 or project 5 must be selected but not both. This is because the variables 𝑥2 and 𝑥5 are binary, meaning they can only take the values 0 or 1.

If project 2 is selected, 𝑥2 will be 1 and to satisfy the equation 𝑥5 must be 0, meaning project 5 is not selected. Conversely, if project 5 is selected, 𝑥5 will be 1 and 𝑥2 must be 0, meaning project 2 is not selected.

Therefore, the constraint ensures that only one of the two projects can be selected, fulfilling the condition of the problem.