The Systems Development Life Cycle (SDLC) is a process of creating or altering information systems, and the models and methodologies that people use to develop these systems. Sequential SDLC models, such as （）, focus on complete and correct planning to guide large projects and risks to successful and predictable results.
The traditional model for systems development was that an IT department used (1) which is a process-centered technique, and consulted users only when their input or approval was needed. Compared with traditional methods, many companies find that JAD allows key users to participate effectively in the (2). When properly used, JAD can result in a more accurate statement of system requirements, a better understanding of common goals, and a stronger commitment to the success of the new system. RAD is a team-based techruque that speeds up information systems development and produces a functioning information system. While the end product of JAD is a(an) (3), the end product of RAD is the (4). The RAD model consists of four phases. During the (5), users interact with systems analysts and develop models and prototypes that represent all system processes, outputs, and inputs.
空白（1）处应选择（）A project life cycle is a collection of generally sequential project（）(1) whose name and number are determined by the control needs of the organization or organizations involved in the project. The life cycle provides the basic（） (2) for managing the project, regardless of the specific work involved.
空白（1）处应选择（）The project life-cycle can be described as（）
SDLC was invented by IBM to replace the older Bisynchronous protocol for wide area connections between IBM equipment. A varietion of the (71) protocol called NRM is essentially the same as SDLC. SDLC is (72) protocol like HDLC, Frame Relay or X.25.An SDLC network is made up of (73) that controls all communications, and (74) . It is capable of (75) operation, but almost all practical applications are strictly half duplex.
（75）是（）我来回答:
