PRODUCT FACILITY QTY M1 F1 2 M2 F1 2 M3 F1 3 M1 F2 4 4 M2 F2 2 M3 F2 Continuing with the multi-site production planning model, suppose the interest is to introduce constraints focused on product inventory levels staying above or close to safety stock targets. A Write high-level perspective of the interest B. What variable(s) would need to be added for this extension? C. What constraint(s) would need to be added for this extension? PRODUCT FACILITY QTY M1 F1 2 M2 F1 2 M3 F1 3 M1 F2 4 4 M2 F2 2 M3 F2 Continuing with the multi-site production planning model, suppose the interest is to introduce constraints focused on product inventory levels staying above or close to safety stock targets. A Write high-level perspective of the interest B. What variable(s) would need to be added for this extension? C. What constraint(s) would need to be added for this extension