For each problem below, create a clear ERD showing the relationships (with verb like HAS, MANAGES, etc.), the cardinalities (1:1, 1:M, M:N), and whether the relation is optional or required. For M:N relations, include an appropriate linking table to implement them. Entities should have necessary attributes shown, as can be discerned from the description.

4. Use the following requirements to create an ERD: An INVOICE is written by a SALESREP. Each sales representative can write many invoices, but each invoice is written by a single sales representative. The INVOICE is written for a single CUSTOMER. However, each customer can have many invoices. An INVOICE can include many detail lines (LINE), each of which describes one product bought by the customer. The product information is stored in a PRODUCT entity. The product's vendor information is found in a VENDOR entity