Question $4[20$ marks$]$ A packaging facility has $10$ identical machines. Currently, the plant uses a run$-$to$-$failure strategy, resulting in high repair costs and frequent production stoppages. Management is considering switching to a preventive maintenance strategy. a$)$ Explain how this switch would benefit the facility $(6$ marks$)$ b$)$ Propose a basic PM schedule for the machines, including tasks and intervals $(6$ marks$)$ c$)$ List the key performance indicators $($KPIs$)$ you would use to track the strategy's effectiveness $(4$ marks$)$ d$)$ Identify two possible limitations of preventive maintenance and how you would mitigate them $(4$ marks$)$