Answer:
II and III.
Step-by-step explanation:
The statement which are true include the following;
I. Service involves a much higher degree of customer contact than manufacturing. This is absolutely true and correct because in the manufacturing of goods or services, the workers do not have any form of interaction with the customer but rather they deal with the middlemen such as wholesalers and retailers. However, services completely deals with interacting with customers on daily basis.
II. A model is an abstraction of reality, which is a simplified version of a real phenomenon.