$($a$)$ In many product markets, availability is a key competitive variable, and companies control

production based on inventory adequacy and delivery delay. Draw a $$causal loop diagram$$ to

represent this system that includes the following variables: Orders, Inventory, Product

Attractiveness, Backlog of Unfilled Orders, Product Availability, Desired Production, and

Production. Add Delays when necessary. Also mark the polarities $(+$ and $-)$ of the relationships

and the nature of the feedback loops $($i$.$e$.$ balancing or reinforcing, with a B and R$).$ Assume any

additional information that is not provided. $(6\%)$