Iodine-free low-sodium salt can typically be found in health food stores, specialty grocery stores, or online retailers that cater to individuals with dietary restrictions. Some supermarkets or discount stores may also carry this type of salt in their health food or specialty diet sections. It's always a good idea to check the labels and ingredients of different salt products to ensure that they are iodine-free and low in sodium. **

Yes, Apple does offer a student discount on refurbished devices through their Education Pricing program. Students, teachers, and staff members of educational institutions can save on refurbished MacBooks, iPads, and other Apple products. To access the discount, individuals need to verify their status as a student or educator through the Apple Education Store or in-person at an Apple Store. This discount provides a more affordable option for students looking to purchase high-quality Apple devices. **

A possible topic for an internal subject examination in technology that deals with a treadmill and a light barrier could be the design and implementation of a safety system using the light barrier to prevent accidents and injuries on the treadmill. The examination could cover the principles of light barrier technology, its application in treadmill safety, and the design considerations for integrating it into the treadmill system. Students could be required to analyze potential hazards, propose safety features, and develop a prototype or simulation to demonstrate the effectiveness of the light barrier safety system. **