Input: Article: The Compact Disc is an evolution of LaserDisc technology, where a focused laser beam is used that enables the high information density required for high-quality digital audio signals. Prototypes were developed by Philips and Sony independently in the late 1970s. In 1979, Sony and Philips set up a joint task force of engineers to design a new digital audio disc. After a year of experimentation and discussion, the Red Book CD-DA standard was published in 1980. After their commercial release in 1982, compact discs and their players were extremely popular. Despite costing up to $1,000, over 400,000 CD players were sold in the United States between 1983 and 1984. The success of the compact disc has been credited to the cooperation between Philips and Sony, who came together to agree upon and develop compatible hardware. The unified design of the compact disc allowed consumers to purchase any disc or player from any company, and allowed the CD to dominate the at-home music market unchallenged.

Now answer this question: To what does the compact disc owe its prosperity?

Output: the cooperation between Philips and Sony

Input: Article: Past problems with hydraulic elevators include underground electrolytic destruction of the cylinder and bulkhead, pipe failures, and control failures. Single bulkhead cylinders, typically built prior to a 1972 ASME A17.1 Elevator Safety Code change requiring a second dished bulkhead, were subject to possible catastrophic failure. The code previously permitted only single-bottom hydraulic cylinders. In the event of a cylinder breach, the fluid loss results in uncontrolled down movement of the elevator. This creates two significant hazards: being subject to an impact at the bottom when the elevator stops suddenly and being in the entrance for a potential shear if the rider is partly in the elevator. Because it is impossible to verify the system at all times, the code requires periodic testing of the pressure capability. Another solution to protect against a cylinder blowout is to install a plunger gripping device. One commercially available is known by the marketing name "LifeJacket". This is a device which, in the event of an uncontrolled downward acceleration, nondestructively grips the plunger and stops the car. A device known as an overspeed or rupture valve is attached to the hydraulic inlet/outlet of the cylinder and is adjusted for a maximum flow rate. If a pipe or hose were to break (rupture), the flow rate of the rupture valve will surpass a set limit and mechanically stop the outlet flow of hydraulic fluid, thus stopping the plunger and the car in the down direction.

Now answer this question: Underground electrolytic malfunctions in hydraulic elevators can result in the destruction of what? 

Output: the cylinder and bulkhead

Input: Article: Chain department stores grew rapidly after 1920, and provided competition for the downtown upscale department stores, as well as local department stores in small cities. J. C. Penney had four stores in 1908, 312 in 1920, and 1452 in 1930. Sears, Roebuck & Company, a giant mail-order house, opened its first eight retail stores in 1925, and operated 338 by 1930, and 595 by 1940. The chains reached a middle-class audience, that was more interested in value than in upscale fashions. Sears was a pioneer in creating department stores that catered to men as well as women, especially with lines of hardware and building materials. It deemphasized the latest fashions in favor of practicality and durability, and allowed customers to select goods without the aid of a clerk. Its stores were oriented to motorists – set apart from existing business districts amid residential areas occupied by their target audience; had ample, free, off-street parking; and communicated a clear corporate identity. In the 1930s, the company designed fully air-conditioned, "windowless" stores whose layout was driven wholly by merchandising concerns.

Now answer this question: How many stores was Sears operating in 1940?

Output:
595