The minerals that make up rocks give them their unique properties. Based on Nguyen's results, do you think that any of the three rocks have the exact same mineral makeup, or are they three different types of rock? Explain your answer.

29.1-12=17.1the answer is this one

The  grandmother cell  is a hypothetical  neuronthat represents a complex but specific concept or object.[1]  it activates when a person "sees, hears, or otherwise sensibly discriminates"[2]  a specific entity, such as his or her grandmother. the term was in use at least as early as 1966 amongst staff and students in the department of experimental psychology, university of cambridge, england. a similar concept, that of the  gnostic neuron, was proposed two years later

The density would be 1.622