5. Pick up the correct statement from the following :
Options
A. The first man-made satellite, Sputnikl' was launched on 4th October, 1957
B. The United State's Explorer 6 transmitted the first picture of the earth in August 1959
C. Television Infrared Observation Satellite (TIROS) designed for meteorological observations, started systematic earth observations from space from 1, April, 1960
D. U.S.A.'s highly secret mission CORONA started the collection of intelligence photograpy in 1960
6. If electric permittivity and magnetic permeability of the medium are respectively ? and ?, then the velocity (Cm) of the electromagnetic wave in the medium is given by :
7. Consider the following statements regarding the satellite imaging : 1. The satellite orbit is fixed in the inertial space 2. During successive across-track imaging, the earth rotates beneath the sensor 3. The satellite images a skewed area Which one of the following statements is/are correct?