A cable that can be used for bidirectional power transmission between a vehicle provided with a driving power source and a power consumer includes: a receiving unit that: communicates with a power-amount acquiring device that is installed at the power consumer, and acquires an amount of power transferred between the power consumer and a power network; and receives identification information of the power consumer; a measuring unit that measures a transmission power amount of power transmitted between the vehicle and the power consumer through the cable; and a transmission information sending unit that sends, to an external managing apparatus that manages an amount of power transmission between the vehicle and the power consumer, the identification information of the power consumer, and information indicating the transmission power amount measured by the measuring unit.