How much energy does an electron have initially in the n=4 excited state? What is the change in energy if the electron from the n=4 excited state drops to the ground state?

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

7is b8 is d9 is c10 is a11 is d