6.2 km =  6.2 x 1 000 = 6 200 m

0.4 hm = 0.4 x 100 = 40 m

38 cm  = 38 x  0.01 = 0.38 m

73 mm = 73 x 0.001 = 0.073 m

4 700 km  = 4 700 000 m

13 cm = 0.13 m