**Environmental and Economic Benefits of Stainless Steel Water Bottles**

**Part A:** The main disadvantage of single-use plastic bottles is that they generate a large amount of plastic waste. Since the plastic used for these bottles is not recyclable in the students’ area, the bottles end up in landfills or the environment, where they take hundreds of years to decompose. This leads to pollution, harms wildlife, and contributes to the global plastic waste problem. --- **Part B:** By using stainless steel water bottles, students eliminate the need to use and dispose of a plastic bottle every day. Over 30 days, each of the 1,000 students would have used and discarded 30,000 plastic bottles. With reusable stainless steel bottles, that waste is avoided, dramatically reducing the amount of plastic entering landfills and the environment. In addition, manufacturing fewer single-use plastic bottles reduces the demand for raw resources and energy used in production and transportation, lowering overall environmental impact. --- **Part C:** From a cost perspective, a stainless steel bottle costs $25, which is about the same as buying 10 single-use plastic bottles ($2.50 each). However, over 30 days, a student would spend $75 if they continued buying a new plastic bottle every day. By purchasing a stainless steel bottle, each student spends only $25 for the month, saving $50 over 30 days. The bottle can also be used for many months or years, meaning further savings over time. Therefore, choosing a stainless steel bottle is a smart financial decision for each student.