This task involves creating answers to complex questions, from a given passage. Answering these questions, typically involve understanding multiple sentences. Make sure that your answer has the same type as the "answer type" mentioned in input. The provided "answer type" can be of any of the following types: "span", "date", "number". A "span" answer is a continuous phrase taken directly from the passage or question. You can directly copy-paste the text from the passage or the question for span type answers. If you find multiple spans, please add them all as a comma separated list. Please restrict each span to five words. A "number" type answer can include a digit specifying an actual value. For "date" type answers, use DD MM YYYY format e.g. 11 Jan 1992. If full date is not available in the passage you can write partial date such as 1992 or Jan 1992. If you find multiple spans, please add them all as a comma separated list. Please restrict each span to five words.

Q: Passage: Salks vaccine was then used in a test called the Francis Field Trial, led by Thomas Francis, Jr., the largest medical experiment in history at that time. The test began with about 4,000 children at Franklin Sherman Elementary School in McLean, Virginia, and eventually involved 1.8 million children, in 44 states from Maine to California. By the conclusion of the study, roughly 440,000 received one or more injections of the vaccine, about 210,000 children received a placebo, consisting of harmless culture media, and 1.2 million children received no vaccination and served as a control group, who would then be observed to see if any contracted polio. The results of the field trial were announced 12 April 1955 (the tenth anniversary of the death of President Franklin D. Roosevelt, whose Franklin D. Roosevelts paralytic illness was generally believed to have been caused by polio). The Salk vaccine had been 60-70% effective against PV1 (poliovirus type 1), over 90% effective against PV2 and PV3, and 94% effective against the development of bulbar polio. Soon after Salks vaccine was licensed in 1955, childrens vaccination campaigns were launched. In the U.S, following a mass immunization campaign promoted by the March of Dimes, the annual number of polio cases fell from 35,000 in 1953 to 5,600 by 1957. By 1961 only 161 cases were recorded in the United States. 
Question: How many states chose not to particpate in the Salks vaccine? 
Answer type: Number 

A: 6.
****
Q: Passage: Constantinople had been an imperial capital since its consecration in 330 under Roman Emperor, Constantine the Great. In the following eleven centuries, the city had been besieged many times but was captured only once: during the Fourth Crusade in 1204.:304 The crusaders established an unstable Latin state in and around Constantinople while the remaining empire splintered into a number of Byzantine successor states, notably Nicaea, Epirus and Trebizond. They fought as allies against the Latin establishments, but also fought among themselves for the Byzantine throne. The Nicaeans eventually reconquered Constantinople from the Latins in 1261. Thereafter, there was little peace for the much-weakened empire as it fended off successive attacks by the Latins, the Serbians, the Bulgarians, and, most importantly, the Ottoman Turks. The Black Plague between 1346 and 1349 killed almost half of the inhabitants of Constantinople. The city was severely depopulated due to the general economic and territorial decline of the empire, and by 1453 consisted of a series of walled villages separated by vast fields encircled by the fifth-century Theodosian walls. By 1450 the empire was exhausted and had shrunk to a few square miles outside the city of Constantinople itself, the Princes' Islands in the Sea of Marmara, and the Peloponnese with its cultural center at Mystras. The Empire of Trebizond, an independent successor state that formed in the aftermath of the Fourth Crusade, also survived on the coast of the Black Sea. 
Question: In eleven centuries, how many times was Constantinople captured? 
Answer type: Number 

A: 1.
****
Q: Passage: Coming off their win over the Steelers the Jets played an interconference duel with the Bears. In the first quarter the Jets trailed early as kicker Robbie Gould got a 37-yard field goal, followed by Matt Forte getting a 22-yard TD run. The Jets pulled ahead with RB Shonn Greene getting a 3-yard TD run, followed by CB Dwight Lowery returning an interception 20 yards for a touchdown, followed by RB LaDainian Tomlinson getting a 3-yard TD run letting the Jets lead 21-10. The lead was narrowed as QB Jay Cutler scrambled 2 yards for a touchdown, but was soon extended as kicker Nick Folk made a 26-yard field goal. They trailed again with Cutler completing a 40 and a 25-yard TD pass to wide receivers Devin Hester and Johnny Knox respectively, but soon were able to tie the game with QB Mark Sanchez throwing a 23-yard TD pass to WR Santonio Holmes. The Bears escaped the tie with Cutler finding Knox again on a 26-yard TD pass. The Jets tried to come back, but only came away with a 34-yard field goal from Folk. When the Jets got the ball back, Sanchez threw a pass intended for Holmes, only to be intercepted by safety Chris Harris with 0:58 to go. With the loss, the Jets fell to 10-5, but clinched a playoff berth when the Jaguars lost to the Redskins.. 
Question: How many touchdowns between 19 and 30 yards were scored? 
Answer type: Number 

A:
5.
****