input: After the success of The Johnstown Flood, two new publishers offered him contracts, one to write about the Great Chicago Fire and another about the San Francisco earthquake. Simon & Schuster, publisher of his first book, also offered McCullough a contract to write a second book. Trying not to become "Bad News McCullough", he decided to write about a subject showing "people were not always foolish and inept or irresponsible." He remembered the words of his Yale teacher: "[Thornton] Wilder said he got the idea for a book or a play when he wanted to learn about something. Then, he'd check to see if anybody had already done it, and if they hadn't, he'd do it." McCullough decided to write a history of the Brooklyn Bridge, which he had walked across many times.  To me history ought to be a source of pleasure. It isn't just part of our civic responsibility. To me it's an enlargement of the experience of being alive, just the way literature or art or music is.  - David McCullough  He also proposed, from a suggestion by his editor, a work about the Panama Canal; both were accepted by the publisher. Critics hailed The Great Bridge (1972) as "the definitive book on the event."  Five years later, The Path Between the Seas: The Creation of the Panama Canal was released, gaining McCullough widespread recognition. The book won the National Book Award in History, the Samuel Eliot Morison Award, the Francis Parkman Prize, and the Cornelius Ryan Award. Later in 1977, McCullough travelled to the White House to advise Jimmy Carter and the United States Senate on the Torrijos-Carter Treaties, which would give Panama control of the Canal. Carter later said that the treaties, which were agreed upon to hand over ownership of the Canal to Panama, would not have passed had it not been for the book.

Answer this question "What led to him gaining"
output: After the success of The Johnstown Flood, two new publishers offered him contracts, one to write about the Great Chicago Fire and another about the San Francisco earthquake.

input: While recording his debut album in 2004, Songz released multiple mixtapes under the alias Prince of Virginia. One of the mixtapes featured an "answer track" to R. Kelly's "Trapped in the Closet", entitled "Open the Closet". The song gave Songz some notoriety. His debut album, I Gotta Make It was released on July 26, 2005. It debuted at #20 on the Billboard 200, selling 40,000 copies in its first week of sales. It has sold 300,000 records in the US. Songz's debut single, Gotta Make It, featuring Twista, was released in March 2005 and reached #87 on the Billboard Hot 100 and #21 on the Hot R&B/Hip-Hop Songs. It garnered success in the R&B/urban community but failed to make a mark in mainstream music. The album's second and final single, Gotta Go, was released in July 2005 and reached #67 on the Hot 100 and #11 on the Hot R&B/Hip-Hop Songs chart, becoming even more successful than his debut single in the R&B/urban community and in the mainstream community. After promotion for his debut concluded, he was featured on the lead single from Twista's fifth album, The Day After. The single, "Girl Tonite", reached #14 on the Hot 100 and #3 on the Hot R&B/Hip-Hop Songs chart, becoming a huge hit.  In mid-2006, Songz began work on a follow-up album to his debut with longtime collaborator Troy Taylor and also employed successful Bryan-Michael Cox, Danja, Stargate and R. Kelly to help create the album. Trey aimed for the album to be more mainstream-oriented than his debut album. His second studio album, Trey Day, was released on October 2, 2007. The album reached #11 on the Billboard 200, selling 73,000 copies in its first week. It has since sold 400,000 records in the US, becoming his second album not to be certified by the RIAA. The album was going to be released on May 8, 2007, but was continually delayed in order for a successful single to precede the album, as the lead single failed to impact charts.  His second album was preceded by the lead single, "Wonder Woman", which was released in February 2007. It reached #54 on the Hot R&B/Hip-Hop Songs chart, but failed to impact the Hot 100. Because of the single's failure, his second album was delayed from May 2007 to October 2007. The album's second single, "Can't Help but Wait", was released in August 2007 and was released to promote his second album and the film Step Up 2 the Streets soundtrack as a single for it. The single reached #14 on the Hot 100, and #2 on the Hot R&B/Hip-Hop Songs chart. It became Songz's first Top 20 hit on the Hot 100, and helped to boost his second album's sales. The single was also nominated for Best Male R&B Vocal Performance at the 2008 50th Grammy Awards. The third single from the album, "Last Time", was released in January 2008 and reached #69 on the Hot 100, and #9 on the Hot R&B/Hip-Hop Songs chart. The fourth and final single from the album, "Missin' You", was released in May 2008, but failed to chart completely. In mid-2008, Songz was nominated for a BET Award for Best Male R&B Artist but did not win the award.

Answer this question "How many copies of album were released?"
output:
It has since sold 400,000 records in the US,