CSP Study Guide

Which statement is true about computing devices in a computer network?

Each computing device must be able to send data to the other computing devices.

Which of these values can be stored in a single bit?

0

Which of the following is a single byte of digital information?

10101101

A bunch of computer scientists take over an island and start their own country. They want the license plates to use binary numbers. There's space for 7 digits on each license plate and the first plate starts at 000000000000000000000. How many unique license plates can their country support?

128

VSCII a character encoding scheme developed in the 1990s in order to encode text written in Vietnamese. VSCII uses one byte to encode each character. This binary data is a VSCII encoding of a single Vietnamese word: How many characters are encoded in that binary data?

2

Your classmate constructs a simple computer that adds numbers. There are 5 wires for inputting the first number, and the wires are currently "on", "on", "off, "on", "off", or 110101101011010 in binary. What decimal number does that represent?

26

MIK is a character encoding scheme that can encode text written in Bulgarian. MIK uses one byte to encode each character. This binary data is a MIK encoding of a single Bulgarian word: How many characters are encoded in that binary data?

3

How many bits are in 4 bytes?

32 bits

Ayleen is a software developer for a 3D animation studio and is in charge of creating a program to render the animations. When she ran her first version of the program on one of the studio's computers, the program took 48 minutes to render 12 frames. To improve the performance, she parallelized the program, rendering each frame in parallel. When she ran the parallelized program on the same computer, it took an average of 6 minutes to complete. What is the speedup of the parallel solution?

8

Which of these best describe what a binary digit can store?

A binary digit can store one of two values, 0 or 1.

A programmer working for the US government is tasked with writing a program to detect fraudulent voter registration. The programmer tries to run the program on their work computer and realizes the computer is too slow to process all of the voter registration records in time for the next election. They decide to use distributed computing to improve the performance. How could a distributed computing solution help?

A distributed computing solution can analyze multiple registration records at once by using multiple computers.

Which of the following is the best description of an IP address?

A number assigned to a computing device that can receive data on the Internet

A team of researchers is studying the rate of glaciers melting in the Himalayas over the last three decades and discovers a recent increase in the melting rate. The research team is considering where to publish their research, either in a conventional journal or an open access journal. In terms of access, who would benefit the least from the decision to publish in an open access journal?

A researcher at a top-tier university

Which of these situations describes a computer network?

A video gaming club sets up six powerful computers in a room and connects them with Ethernet cables to a router. The club members play multi-player games together.

Many people worry about what would happen if either the Internet or the World Wide Web went down (if they suffered a complete outage and were unreachable). Which of these predictions is correct?

If the Internet went down, the World Wide Web would also go down, since the WWW relies on the Internet protocols.

A musician decides to make a digital recording of their concert so that they can share it with fans that cannot attend the concert in person. What is true about the process of converting the concert's audio waves into a digital recording?

If the recording equipment uses a very small sampling interval, the digital recording will be a very good representation but will not contain every detail.

Railways have devices called "axle counters" that count up how many train axles have passed by, and helps decide if a train has fully passed part of a track. However, because of a bug in the design of the axle counter logic, a train that has exactly 256 axles will result in a count of 0, and its existence will be ignored. Thus, trains that run on these buggy railways must have less than 256 axles. What is the most likely cause of this bug?

Integer overflow error

In 2015, the nation of Burundi had an average bandwidth per Internet connection of 11.24 kb/s. In 2016, their average bandwidth was 6.91 kb/s. Which statement is true based on those statistics?

Internet connections in Burundi in 2015 were able to transfer more bits per second than connections in Burundi in 2016.

Amazon describes their web services platform like this: Amazon Web Services (AWS) is a highly reliable, scalable, low-cost infrastructure platform in the cloud that powers hundreds of thousands of enterprise, start-up and public sector business with organizations in over 190 countries around the world. What does it mean for the platform to be scalable?

It continues operating when experiencing traffic surges.

Which of these is a way that the Internet Protocol (IP) contributes to Internet communications?

It describes how to route packets of data around the Internet, from router to router, based on a destination address.

In what situations is the Internet Protocol (IP) used?

It is used every time that two computing devices send data to each other over the Internet.

Sariah is writing a research paper for literature class where she must cite many sources. She decides to make a tool to automate the citation process, and comes up with the following algorithm for citing a book: Split author name into first name and last name. Combine last name, comma, first name, and period. Combine title with period, and wrap in italics style. Combine publisher, comma, year published, and period. Combine strings from steps 2-4. After using the algorithm successfully for a single book, she decides to extend it to generate citations for all of her books at once. What structure must be added to the original algorithm so that it can operate on multiple books?

Iteration

Remy is setting up a cooking blog and is deciding whether to use lossy compression algorithms on her photos of yummy meals. What's a good explanation of the benefits and drawbacks to lossy compression algorithms?

Lossy compression algorithms reduce the file size, but the compression is irreversible, so you need to store the original images if you ever want to display the photos at a higher quality.

An algorithm will be used to count how many numbers in a list are multiples of either 5 or 10. For the list of [5, 3, 2, 10, 20, 7], it should count 3 numbers (5, 10, 20). There are two proposals for the algorithm: Algorithm 1: Set value of count to 0. Iterate through each number in the list. If the current number is a multiple of 5 and a multiple of 10, increment count by 1. Algorithm 2: Set value of count to 0. Iterate through each number in the list. If the current number is a multiple of 5, increment count by 1. Then, if the current number is a multiple of 10, increment count by 1. Which of the following best describes the behavior of these algorithms?

Neither algorithms will output the correct count on all inputs, due to issues with under-counting or over-counting multiples.

A startup is developing a new web browser with a focus on accessibility for visually impaired users. The startup founder is considering the benefits and drawbacks of releasing the code online under an open source license. What would be a consequence of releasing the code with an open source license?

Other companies and individuals would be able to view and use the code according to the conditions of the open source license.

Ryland is creating an article about commonly used compression algorithms for an online educational site. He's debating whether to express each algorithm in natural language, flow charts, pseudocode, or C++, a general-purpose programming language. Which of these is a good argument for expressing the algorithm in pseudocode?

Pseudocode doesn't depend on the syntax and subtleties of a particular programming language, so his readers will be able to understand it as long as they know at least one language.

Rafi is developing an application to send urgent information about global health crises over the Internet to hospitals. He is worried about packets getting lost along the way and the effect that will have on the accuracy of the information. What is his best option for dealing with lost packets?

Rafi can use the Transmission Control Protocol for communication, since TCP has ways to recover when packets are lost.

A programmer is writing a software application about birds that will use a variety of data sources. They want to understand which data sources are analog so that they can think carefully about the process of converting the analog data into digital data. Which of these data sources is analog?

The altitude of a bird as it flies through the sky

A computer must adhere to the Internet protocols in order to send data through the Internet. Which of these best describe what it means for a computer to adhere to a protocol?

The computer must send data according to the documented rules of the protocol.

Which of these statements about the digital divide is true?

The digital divide is affected by geography; some areas are harder to connect to the Internet than others.

A software engineer at a mapping company is tasked with coming up with an algorithm to solve a new problem. The engineer is nervous about whether they'll be able to solve it. Which of these outcomes is the least likely?

The engineer may discover that the algorithm is only solvable in a programming language that their company does not use.

A high school provides email addresses to freshman students. The email system typically assigns an email address in the format "[email protected]". However, if a student has the same name as a previous student, the system assigns them a different format. In order to figure out whether an email address is already assigned, the system does a binary search through its list of existing email addresses. Which of these statements is true?

The list of email addresses must be sorted for binary search to work.

Which of these best describes the fault tolerance of routing on the Internet?

There are multiple routes for each IP packet to follow. A packet can be re-routed if a path becomes unavailable.

Consider these files: A 3-second audio recording of a baby's first word. A 30-second video recording of a baby's first steps. Is it possible for the 30-second video recording to have a smaller file size than the 3-second audio recording?

Yes, if the 30-second video is compressed with a lossy compression algorithm.