WorksheetsData Security and Compression
Total questions: 10
Worksheet time: 10mins
Lennox is writing a program that keeps track of the tokens a player has in a game. Lennox decides to store each token a player has collected in a list called tokenList. The tokens are stored in alphabetical order. For example, a player might collect token B first, then token C, and then token A. The list in Lennox’s program would look like this:
tokenList – [A, B, C]
Lennox then uses the tokenList to display which tokens have been collected by the player. Lennox’s program is saved on two computers that have the same configuration. The program is run on each computer. The player on each computer collects the same tokens so the values stored in the tokenList for each program are the same. Which of the following is true about Lennox’s program?
Lennox’s program will not display the correct list of tokens collected for each player if one player collects more tokens than the other player.
Lennox’s program will not display the correct list of tokens collected for a player if the player collects the same token twice.
Reading the items from the tokenList and updating the tokenList have different storage requirements.
D. The programs on each computer take up different amounts of memory and space on the storage device.
Which of the following is a true statement about data compression?
Data compression techniques can be used to reduce the size of a file for storage or transmission.
Data compression techniques can only be used for certain types of data.
Data compression techniques cannot be applied to files being transmitted over the Internet.
Lossy data compression should be used if there may be a need to recover all of the original data from the compressed file.
Milan took a photograph with her high resolution digital camera. Then, she emailed a copy of the picture to herself to use in a school project. When Milan downloaded the picture from her email, she noticed that it did not look as crisp and the colors were not exactly the same. Which of the following could be a possible explanation for difference in image quality?
The picture saved in the email contained fewer pixels than the original image.
The picture saved in the email contained more pixels than the original image.
The picture saved in the email was encrypted. Data encryption causes information loss.
The picture saved in the email was encrypted. Milan needs to decrypt the picture to restore the original image quality.
Janell purchased an app online using his credit card. His purchase data was sent over the Internet in plain text and intercepted by an unknown third party. Several days later Janell noticed purchases were made with his credit card that he did not originate. Which of the following could have helped to prevent these unauthorized purchases?
Metadata about Janell’s purchase should have been added before the purchase data was sent over the Internet.
Janell’s purchase data should have been encrypted before it was transmitted over the Internet.
Janell’s purchase data should have been compressed using a lossy
compression technique before it was transmitted over the Internet.
Janell’s purchase data should have been compressed using a lossless compression technique before it was transmitted over the Internet.
A song is digitally recorded by an artist and saved to a file. Then, the artist runs a program that takes the file as input and produces a new file. The new file does not include any sound data recorded that cannot be heard by the human ear. The artist then saves the new file over the original file. Which of the following is true about the transformation of the digitally recorded song data?
This is a lossy transformation of data that results in a smaller file size.
This is a lossy transformation of data that results in a larger file size.
This is a lossless transformation of data that results in a smaller file size.
This is a lossless transformation of data that results in a larger file size.
Which of these statements highlights a valid privacy concern when working with large data sets?
I. Data from multiple sources could be linked together to discover someone’s identity.
II. For access to location-based services, a user needs to reveal location and identity.
III. CAPTCHA is a popular crowdsourcing technique that can be used to sense if the user is human.
I and II only
I only
I and III only
I, II and III
Which of the following is a true statement about data compression?
Data compression is only useful for files being transmitted over the Internet.
Regardless of the compression technique used, once a data file is
compressed, it cannot be restored to its original state.
Sending a compressed version of a file ensures that the contents of the file cannot be intercepted by an unauthorized user.
There are trade-offs involved in choosing a compression technique for storing and transmitting data.
The colors of the pixels in a digital image are often represented by red, green, and blue values between 0 and 255 (an RGB triplet). A photographer is manipulating a digital image to lighten it because all of the RGB values in the image are less than 100, making it very dark. He does this by adding 20 to the R, G, and B values of each pixel, then overwriting the original image. What type of transformation is the photographer using on the digital image?
Lossless transformation
Lossy transformation
Multiband transformation
Chrome sampling transformation
A programmer is writing a system that is intended to be able to store large amounts of personal data. As the programmer develops the data system, which of the following is LEAST likely to impact the programmer’s choices in designing the structure of the system?
Maintaining privacy of the information stored in the data set.
Scalability of the system.
Structuring the metadata of the information for analysis.
The frequency of a particular item occurring in a data set.
While using image compression algorithms we know that jpeg is a lossy file format for image compression and png files use a lossless compression format.
A software development company is building a custom application for the government. The software will scan images of citizens of the country and store it in a database. The images can then be pulled up with other necessary information as needed.
What would be the image format that can be best suitable
for this software?
PNG
JPEG
Neither PNG or JPEG
Both PNG and JPEG
