Problem: A Yagi-Uda array uses passive elements to greatly increase gain. It is built along a support boom that is pointed toward the signal, and thus sees no induced signal and does not contribute to the antenna's operation. The end closer to the source is referred to as the front. Near the rear is a single active element, typically a half-wave dipole or folded dipole. Passive elements are arranged in front (directors) and behind (reflectors) the active element along the boom. The Yagi has the inherent quality that it becomes increasingly directional, and thus has higher gain, as the number of elements increases. However, this also makes it increasingly sensitive to changes in frequency; if the signal frequency changes, not only does the active element receive less energy directly, but all of the passive elements adding to that signal also decrease their output as well and their signals no longer reach the active element in-phase.
What can take advantage of these elements to add more gain?
The answer is the following: Yagi-Uda array

Problem: From 1988 to 1997, the BBC and Sky Sports had coverage of the FA Cup, the BBC had highlights on Match of the Day and usually one match per round while Sky had the same deal. From 1997 to 2001, ITV and Sky shared live coverage with both having two matches per round and BBC continuing with highlights on Match of the Day. From 2002 to 2008, BBC and Sky again shared coverage with BBC having two or three matches per round and Sky having one or two. From 2008–09 to 2013–14, FA Cup matches are shown live by ITV across England and Wales, with UTV broadcasting to Northern Ireland but STV refusing to show them. ITV shows 16 FA Cup games per season, including the first pick of live matches from each of the first to sixth rounds of the competition, plus one semi-final exclusively live. The final is also shown live on ITV. Under the same 2008 contract, Setanta Sports showed three games and one replay in each round from round three to five, two quarter-finals, one semi-final and the final. The channel also broadcast ITV's matches exclusively to Scotland, after the ITV franchise holder in Scotland, STV, decided not to broadcast FA Cup games. Setanta entered administration in June 2009 and as a result the FA terminated Setanta's deal to broadcast FA-sanctioned competitions and England internationals. As a result of Setanta going out of business ITV showed the competition exclusively in the 2009–10 season with between three and four matches per round, all quarter finals, semi-finals and final live as the FA could not find a pay TV broadcaster in time. ESPN bought the competition for the 2010–11 to 2012–13 season and during this time Rebecca Lowe became the first woman to host the FA Cup Final in the UK.
Does anyone refuse to show them? 
The answer is the following: STV refusing to show them

Problem: In the following two decades after Sianis' ill will, the Cubs played mostly forgettable baseball, finishing among the worst teams in the National League on an almost annual basis. Longtime infielder/manager Phil Cavarretta, who had been a key player during the '45 season, was fired during spring training in 1954 after admitting the team was unlikely to finish above fifth place. Although shortstop Ernie Banks would become one of the star players in the league during the next decade, finding help for him proved a difficult task, as quality players such as Hank Sauer were few and far between. This, combined with poor ownership decisions such as the College of Coaches, and the ill-fated trade of future Hall of Famer Lou Brock to the Cardinals for pitcher Ernie Broglio (who won only 7 games over the next three seasons), hampered on-field performance.
Who was fired during spring training in 1954 after admitting the Cubs were unlikely to finish above fifth place?
The answer is the following: Phil Cavarretta

Problem: The Prussian army was controlled by the General Staff, under Field Marshal Helmuth von Moltke. The Prussian army was unique in Europe for having the only such organisation in existence, whose purpose in peacetime was to prepare the overall war strategy, and in wartime to direct operational movement and organise logistics and communications. The officers of the General Staff were hand-picked from the Prussian Kriegsakademie (War Academy). Moltke embraced new technology, particularly the railroad and telegraph, to coordinate and accelerate mobilisation of large forces.
What entity controlled the Prussian army?
The answer is the following:
the General Staff