CSP Study Guide

1011001010010010 How many bytes long is that sequence of bits?

2

The United States Postal Service (USPS) delivers nearly 200 million pieces of mail every day. Their website and internal operations are powered by many algorithms. Which algorithm's runtime is most likely to be improved by the use of a heuristic?

Calculating an efficient route for a delivery carrier through a city, considering factors like parking space and mail volume

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 these lists correctly counts from 1 to 5 in binary?

00010001, 001000100010, 001100110011, 010001000100, 01010101

Which of these lists correctly orders the binary numbers from smallest to largest?

0001000100010001, 000101010001010100010101, 001001110010011100100111, 0100100001001000

How many bits are in 444 bytes?

32 bits

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.

When do Internet-connected computing devices use the Internet Protocol (IP)?

It is used whenever two computing devices send data to each other over the Internet.

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.

Which statements are true about computing devices? All computing devices are able to run computer programs. All computing devices are capable of being interconnected to form computer networks. All computing devices have ways to store data for later use.

All computing devices are able to run computer programs.

Which of these statements about algorithms is not true?

An algorithm that uses a heuristic will come up with the optimal solution more quickly than an algorithm that does not.

What Does Digital literacy mean.

Basic digital literacy includes the ability to use input and output devices (such as a mouse, keyboard, or touch screen), an understanding of the structure of the digital environment (what files, folders, scrollbars, links, menus, and buttons mean), and the ability to interact with digital information (knowing how to save, delete, open, or select).

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

1

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

11010010

Which of these addresses is the kind used by the Internet Protocol (IP) to identify devices that are connected to the Internet?

242.185.95.235

11000011111100111111101110000001 How many bytes long is that sequence of bits?

4

Which of these situations describes a computer network?

A company gives every employee a desktop computer and connects each of the computers to each other using wires, so that they can quickly transfer files and messages.

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

A number that identifies Internet-connected devices

A data scientist develops an algorithm for analyzing social media data. They're writing a blog post about it, and are hoping that other data scientists will try out the algorithm on their own data. They're debating whether to express the algorithm in natural language, flow charts, pseudocode, or Python, a general-purpose programming language. Which of these is a good argument for expressing the algorithm in Python?

Python can be run on any computer that has a Python interpreter, so others can try out the algorithm with their own data and not worry about translating the algorithm correctly to a language.

Han develops an algorithm to compute the average amount of time that users watch a particular video on Khan Academy. He then realizes that the average is very low, due to a large number of times with duration "0" or "1", and decides that the algorithm should ignore those durations. What structure must be added to the algorithm so that it does not consider those short durations when computing the average?

Selection

A security engineer is developing antivirus software that detects when downloaded programs look similar to known viruses. They would like the software to be able to detect viruses that it's never seen before, by predicting whether or not a program will ever execute malicious code. After a bit of research, the engineer realizes that virus detection is an undecidable problem.

The engineer might come up with an algorithm that correctly predicts the execution of malicious code in some cases, but the algorithm will not be correct all of the time.

ScootALot is a scooter rental service. At the end of each day, they hire contractors to pick up scooters and distribute them optimally around the city. The distribution algorithm considers all the possible locations for the scooters, compares that to the density of customers, and comes up with the optimal location for each scooter. As the company becomes more popular, they realize their algorithm is taking an unreasonable amount of time to come up with optimal scooter locations. What is the best way to improve the run time of the algorithm?

Use a heuristic-based algorithm that suggests good locations for the scooters.

The following algorithm computes the maximum score for a list of final exam scores. Initialize a variable max to the first score in the list. For each score in the list, compare the score to max. If score is greater than max, store score in max Return max. Which building blocks are involved in this algorithm?

Iteration, Sequencing, and Selection

How many bits are in 2 bytes?

16 bits

How many values can a binary digit store?

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

Which of the following kinds of computing devices use the Internet Protocol (IP) when sending data over the Internet? A tablet computer A desktop computer A smartphone

All Three

Makayla is developing software for an animal shelter. After some research, she comes up with this algorithm for calculating the number of daily calories required for a dog: Calculate the Resting Energy Requirement (RER) by raising the dog's weight to the 3/4 power and multiplying the result by 70 If the dog is neutered, multiply RER by 1.6 Otherwise, multiply RER by 1.8 After verifying the algorithm comes up with a reasonable number for a single dog, she decides to extend it to compute the total calories needed for all the dogs in the shelter each day. What structure must be added to the original algorithm so that it can compute the calories for multiple dogs?

Iteration

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.

Serena operates a security camera that stores still images in timestamped filenames. The camera can generate thousands of images each day, and she needs a way to find the image corresponding to a particular timestamp. She comes up with this algorithm: Start with a list of the image filenames, sorted from oldest to newest. Set min to 1 and max to the number of images. Set index to the average of max and min, rounded down so that it is an integer. Check the filename located at that index in the list. If the filename equals the desired timestamp, the search is done! Exit the algorithm. If the filename is older than the desired timestamp, set min to be one larger than index. If the filename is newer than the desired timestamp, set max to be one smaller than index. Go back to step 3. Which statements are true about this algorithm?

It is more efficient than a linear search and It implements a binary search.