The main scale, on a travelling microscope, has 20 divisions each between its different ‘centimeter marks’. The vernier scale, attached to it, has 50 divisions and these coincide with 49 divisions of the main scale. The value of one vernier scale division, and the least count of this vernier, are equal, respectively, to
(1) 0.049 mm and 0.001 mm
(2) 0.049 mm and 0.001 cm
(3) 0.049 cm and 0.001 mm
(4) 0.049 cm and 0.001 cm