Imagine you are tasked with designing the database for an e$-$commerce platform. Given the specific requirements below, answer the following questions:

Customers can place multiple orders, and each order consists of one or more products. Each product belongs to a specific category. Customers can maintain multiple shipping addresses for their orders.

a$.$ Determine the list of entities and their attributes.

b$.$ Identify the primary key of each of the entity and describe the justification for the same.

c$.$ Determine the relationships between those entities along with the mapping cardinality. Describe your justification for the mapping cardinality finalized by you.

d$.$ Determine two more requirements in terms of this e$-$commerce retail application and describe them. Accordingly, list the entities, attributes and relationships.$\backslash$