What are the importance of primary keys and dry-run testing, and list three electronic data processing modes?

You're on a roll — Here are the solutions for the questions from the image: Question 10: What is a primary Key A primary key is a column or a set of columns in a database table that uniquely identifies each record (row) in that table. It must contain unique values for each record and cannot have null values. Question 11: Explain any two Importance of a Primary Key • Uniqueness and Identification: A primary key ensures that every record in a table can be uniquely identified, preventing duplicate entries and maintaining data integrity. • Establishing Relationships: Primary keys are crucial for establishing relationships between different tables in a relational database. They serve as foreign keys in other tables, linking related data. Question 12: State a circumstance under which dry-run testing is performed when developing a program Dry-run testing is performed before the program is actually executed on a computer. It is typically done by a programmer manually tracing the logic of the code with sample input data, step-by-step, to identify logical errors, design flaws, or incorrect algorithms early in the development cycle, often during the coding or debugging phase. Question 13: List three electronic data processing modes used in computers 1. Batch Processing: Data is collected over a period and processed in groups or batches at a scheduled time. 2. Real-time Processing: Data is processed immediately as it is input, providing instant results or updates. 3. Online Processing: Data is processed interactively, often through a network, allowing users to directly interact with the system and receive immediate responses. Question 14: Distinguish between data collection and data capture as used in data processing Data Collection refers to the broader process of gathering raw facts and figures from various sources, such as surveys, observations, or existing documents. It's about obtaining the initial data. Data Capture is the specific process of converting the collected raw data into a machine-readable format that can be directly input into a computer system for processing. This often involves using input devices like scanners, keyboards, or sensors. Question 15: Given the binary number 10101110111011, determine the number of Step 1: Count the total number of bits in the given binary number. The binary number is 10101110111011. Counting the digits, there are 14 bits. a) nibbles Step 2: Calculate the number of nibbles. A nibble consists of 4 bits. Number of nibbles = Total number of bitsBits per nibble Number of nibbles = (14)/(4) = 3.5 The number of nibbles is 3.5. b) Bytes Step 3: Calculate the number of bytes. A byte consists of 8 bits. Number of bytes = Total number of bitsBits per byte Number of bytes = (14)/(8) = 1.75 The number of bytes is 1.75. What's next?