In this task, you're expected to write answers to questions involving multiple references to the same entity. The answer to the question should be unambiguous and a phrase in the paragraph. Most questions can have only one correct answer.

Input: Consider Input: Passage: Although the publicity generated by Five Leaves Left was minor, Boyd was keen to build on what momentum there was. Drake's second album, 1971's Bryter Layter, again produced by Boyd and engineered by John Wood, introduced a more upbeat, jazzier sound.Disappointed by his debut's poor commercial performance, Drake sought to move away from his pastoral sound, and agreed to Boyd's suggestions to include bass and drum tracks. "It was more of a pop sound, I suppose," Boyd later said. "I imagined it as more commercial." Like its predecessor, the album featured musicians from Fairport Convention, as well as contributions from John Cale on two songs: "Northern Sky" and "Fly". Trevor Dann noted that while sections of "Northern Sky" sound more characteristic of Cale, the song was the closest Drake came to a release with chart potential. Cale used heroin during this period, and his older friend Brian Wells suspected that Drake was also using.Boyd and Wood were confident that Bryter Layter would be a success, but it sold fewer than 3,000 copies. Reviews were again mixed: while Record Mirror praised Drake as a "beautiful guitarist—clean and with perfect timing, [and] accompanied by soft, beautiful arrangements", Melody Maker described the album as "an awkward mix of folk and cocktail jazz".Soon after its release, Boyd sold Witchseason to Island Records, and moved to Los Angeles to work with Warner Brothers to develop film soundtracks. The loss of his mentor, coupled with the album's poor sales, led Drake into further depression. His attitude to London had changed: he was unhappy living alone, and visibly nervous and uncomfortable performing at a series of concerts in early 1970. In June, Drake gave one of his final live appearances at Ewell Technical College, Surrey. Ralph McTell, who also performed that night, remembered: "Nick was monosyllabic. At that particular gig he was very shy. He did the first set and something awful must have happened. He was doing his song 'Fruit Tree' and walked off halfway through it."In 1971, Drake's family persuaded him to visit a psychiatrist at St Thomas's Hospital, London. He was prescribed antidepressants, but felt uncomfortable and embarrassed about taking them, and tried to hide the fact from his friends. He worried about their side effects and was concerned about how they would react with his regular cannabis use.Island Records urged Drake to promote Bryter Layter through interviews, radio sessions and live appearances. Drake, who by this time was smoking what Kirby described as "unbelievable amounts" of cannabis and exhibiting "the first signs of psychosis", refused. Disappointed by the reaction to Bryter Layter, he turned his thoughts inwards, and withdrew from family and friends. He rarely left his flat, and then only to play an occasional concert or to buy drugs. His sister recalled: "This was a very bad time. He once said to me that everything started to go wrong from [this] time on, and I think that was when things started to go wrong.". 
Question: What is the last name of the person who agreed to include bass and drum tracks?

Output: Northern Sky.


Input: Consider Input: Passage: Half of Minneapolis–Saint Paul residents work in the city where they live. Most residents drive cars, but 60% of the 160,000 people working downtown commute by means other than a single person per auto. The Metropolitan Council's Metro Transit, which operates the light rail system and most of the city's buses, provides free travel vouchers through the Guaranteed Ride Home program to allay fears that commuters might otherwise be occasionally stranded if, for example, they work late hours.On January 1, 2011, the city's limit of 343 taxis was lifted.Minneapolis currently has two light rail lines and one commuter rail line. The METRO Blue Line LRT (formerly the Hiawatha Line) serves 34,000 riders daily and connects the Minneapolis–Saint Paul International Airport and Mall of America in Bloomington to downtown. Most of the line runs at surface level, although parts of the line run on elevated tracks (including the Franklin Avenue and Lake Street/Midtown stations) and approximately 2 miles (3.2 km) of the line runs underground, including the Lindbergh terminal subway station at the airport. 
Question: What is the former name of the line that has a terminal subway station at the airport?

Output: Hiawatha Line.


Input: Consider Input: Passage: Administrators at Mildew College, an all-girl school, are begging the school's largest benefactor, Mrs. Catsby, to provide an athletic fund for the school. She does not approve of girls playing sports, and informs the administrators that the money will be used for the salaries of the three new Teutonic professors that are arriving that day. Meanwhile, the Stooges have just started a new job as servicemen at a service station, with a strong held belief of "super soyvice!" When they get a customer (three older German men driven by a chauffeur), they proceed to provide their own inept brand of service, angering the men. The mayhem ends when Curly accidentally puts gasoline in the radiator and Moe checks it with a match. The resulting explosion wrecks the car and prompts the Stooges to flee in a nearby ice cream truck that they had coincidentally thrown the German men's suitcases into. Curly climbs in the back while Moe and Larry are in the front.
The Stooges finally stop when they run out of gas. Moe and Larry realize that Curly is still in the back of the truck and is now frozen solid. They thaw him out by tying him to a tree branch over an open fire. This works fine until Curly wakes up on fire and jumps into a nearby lake. When Moe and Larry try to help him out, he pulls them in with him. Now soaked, the boys decide to see if there are any dry clothes in the suitcases they had thrown into the truck.
The suitcases, it turns out, belong to the three new professors for Mildew College, and as the boys, now decked in their gowns and mortarboards, try to hitch a ride, Mrs. Catsby spots them and picks them up, bringing them to the school. During the introductions of the "new professors," a student gets wise with a nonplussed Larry, and in order to test their "mental coordination", Moe begins a rendition of "Swingin' the Alphabet", which starts off fine and eventually transcends into a jazzy, off-time performance. 
Question: What causes Curly to freeze?


Output: ice cream truck.