An astronaut is connected to her spacecraft by a 25-m-long tether cord as she and the spacecraft orbit Earth in a circular path at a speed of 3.0 x103 m/s. At one instant, the voltage gauged between the ends of a wire embedded in the cord is gauged to be 0.45V. Assume the long dimension of the cord is perpendicular to the vertical component of Earth's magnetic field at that instant. (a) What is the magnitude of the vertical component of Earth's field at this location? (b) Does the gauged voltage change as the system moves from one location to another?