Final answer:
The question involves high school level physics topics related to electromagnetic fields and induced emf, and requires more context to provide a specific answer.
Step-by-step explanation:
The question appears to involve concepts from physics, specifically electromagnetism, and is likely related to calculating electric fields, magnetic fields, and induced electromotive force (emf). Though the question presented seems to be a mix of multiple different problems, a theme common to the fragments pertains to the effects within a magnetic field, such as how a moving conductor in a magnetic field induces an emf, how to calculate the electric field due to a charge distribution, and how changing electric fields can lead to displacement currents. These particular topics are usually covered in a high school or college level physics course, specifically in sections dealing with Maxwell's equations and Faraday's law of induction. To properly address the student's question, more contextual information and clarification would be needed.