• k(キロ): 103, M(メガ): 106, G(ギガ): 109, T(テラ): 1012,P(ペタ): 1015
  • 1 t = 103 kg = 106 g = 1 Mg
  • 1 Tg = 103 Gg = 106 Mg = 1 Mt = 10-3 Gt
  • 1 Gt = 1000 Tg = 1 Pg
  • 1 億t = 108 t = 102 Mt = 10-1 Gt
  • 1 億t = 108 t = 1014 g = 102 Tg