The present invention discloses a protocol version negotiation method, a mobile terminal and a base station. The image forming unit uses a plurality of different color developing agents to form a color image on a recording medium. The leaf members provide hook and loop fasteners on the first and second side thereof for attachment to one another. A phase component of the result, which is defined as 20arg is determined, from which the orientation angle is calculated. The mask portion includes a recessed mouth section on the inner portion thereof. Retrieving the content may include using one or more categories relevant to the entity to identify the content.