Read the text and fill articles, “any” in the gaps where necessary. Goal line technology, Hawk Eye Hawk-Eye’s system uses six cameras, focusing on __each goal, to track __ ball on __ pitch. __ system’s software uses “triangulation” to pinpoint __ exact location of __ ball. If it crosses __ goal-line, __ encrypted radio signal is sent to __ referee’s wristwatch to indicate __ goal has been scored. __ whole process takes less than __ second to complete. GoalRef uses __ microchip implanted in __ ball and __ use of __low magnetic waves around __ goal. __ system then detects __ change in __ magnetic field on or behind __ goal-line to determine if __ goal has been scored. __ process takes less than one second, with __ result electronically relayed to __ referee. http://www.bbc.co.uk/sport/0/football/17725886