Which of these challenges is unique to the process of designing prostheses as opposed to engineering other technologies? - Knowing how a material will fail
- Using the engineering process
- Identifying a need for the technology
- Predicting how a technology will interact with human tissue

predicting how a tech will interact with human tissue.

Explanation:

thats not really common except for in the medical field.

nacl or sodium chloride is an ionic compound. this is because an ionic compound pertains to a compound that consists of positively and negatively charged ions. in this case, na (sodium) has a tendency to lose one electron when it reacts with with other atoms, so the resulting sodium ion contains 11 protons and 10 electrons, thus making it positively charged (na+), when chlorine reacts, it usually gains one electron to form an ion called chloride, thus making it negatively charged ( since the ions are oppositely charged, they attract.