Numerical Response 50. The minimum potential difference through which an electron must be accelerated to produce an X-ray of energy 1.62 x 104 ev, expressed in scientific notation, is a.bc x 10d V. The value of a, b, c, and d are , and (Record your four-digit answer in the numerical-response section on the answer sheet.) Numerical Response 51. An X-ray tube operates at an electrical potential difference of 1.50 x 105 V. The minimum wavelength of the X-ray radiation it produces can be expressed in scientific notation as a.b x 10 - cd m. The value of a, b, c, and d are , and (Record your four-digit answer in the numerical-response section on the answer sheet.)