application

 I would talk about gathering stakeholders together, mention the different functional areas, talk about the type of meeting you might have, talk about analysis you might do, and how you would prepare a persuasive presentation.

In the job, how would you make the case for a significant change to a product area? Please cover in general terms who you would involve and what approach you would take.
Is that the whole question, LOOP, or did you simplify it for us? Normally, I'm a big fan of simplifying stuff; I don't know anything about petroleum chemistry, so if you asked me a question about petroleum chemistry, I might get lost in the details. But in this case, your question standing alone doesn't have enough detail for me to be helpful.
What kind of products does this company make? Is the company known for relentlessly improving its products (Lexus cars, IBM) or is the company famous for sticking with a sure thing (Coca-Cola, Guiness beer)?
Any answer should briefly mention company culture, teamwork, and budget. But with only 500 words, you're smart to focus on your part of things. If you're an industrial chemist, talk about how you'd evaluate new formulas. If you're in finance or accounting, talk about budget concerns. If you're in sales, talk about customer feedback and getting longtime customers excited about a revised product.