Which of the following are right regarding to the allowable increase and decrease of the objective function coefficients? (Select all that apply.) They define the range within which the objective function coefficients can change without changing the optimal solution. They define the range within which the objective function coefficients can change without changing the optimal objective function value. They can be used to judge if alternative solutions exist. They can be used to judge if redundant constraints exist. The 100% rule is used to determine if the current objective function value is optimal. if the current objective function value will remain optimal when simultaneous changes happen to the objective function coefficients. if the current solution is 100% optimal. if the current objective function value will remain optimal when one of the objective function coefficients change