A gamma-ray telescope intercepts a pulse of gamma radiation froma magnetar, a type of star with a spectacularly largemagnetic field. The pulse lasts 0.25 s and delivers 7.2 x10-6 J of energy perpendicularly to the94-m2 surface area of the telescope's detector. The magnetar is thought to be 3.28 x 1020 m (about35000 light-years) from earth, and to have a radius of 7.0 x103 m. Find the magnitude of the rms magnetic fieldof the gamma-ray pulse at the surface of the magnetar, assumingthat the pulse radiates uniformly outward in all directions.(Assume a year is 365.25 days.)