Final answer:
Research and development costs can include routine efforts to refine an existing product, periodic alterations to production lines, construction of prototypes, and marketing research for new products.
Step-by-step explanation:
Research and development costs can include activities such as routine efforts to refine an existing product, periodic alterations to existing production lines, construction of prototypes, and marketing research to promote a new product.
For example, routine efforts to refine an existing product can involve the development of new features or improvements to enhance its performance or usability. Periodic alterations to existing production lines may involve upgrading equipment or implementing new manufacturing processes.
Marketing research to promote a new product involves gathering data and insights about the target market and consumer preferences to develop effective marketing strategies. And construction of prototypes involves creating functional models to test and refine new product ideas.