Creative Development and Data | Unit Test

Digital alarm clocks display information and visual indicators to help people wake up on time. Which of the displays could be represented by a single bit? There are exactly two correct answers.

• The "PM"/"AM" indicator

• The current day of the week

• The current hour (1-12)

• The current month (1-12)

• The temperature unit indicator ("C" or "F")

An algorithm will be used to calculate the difference between the smallest and largest values in a list. For the list of [10, 3, 5, 6], it should calculate a difference of 7. There are two proposals for the algorithm:

Algorithm 1: Set 'minVal' to the first value in the list and 'maxVal' to the last value in the list. Iterate through each number in the list. If the number is greater than 'maxVal', store it in 'maxVal'. If the number is less than 'minVal', store it in 'minVal'. Then, set 'maxDiff' to the difference between 'maxVal' and 'minVal'.

Algorithm 2: Set 'minVal' to 1000 and 'maxVal' to 0. Iterate through each number in the list. If the number is greater than 'maxVal', store it in 'maxVal'. If the number is less than 'minVal', store it in 'minVal'. Then, set 'maxDiff' to the difference between 'maxVal' and 'minVal'.

Which of these statements are true about these algorithms?

I. Algorithm 1 does not work on lists where the smallest value is at the start of the list or the largest value is at the end of the list.

II. Algorithm 2 does not work on lists that contain all negative numbers or all numbers greater than 1000.

• I only

• II only

• I and II

• Neither I nor II

A medical diagnosis app lets users track their symptoms. Whenever a user reports a symptom, the app adds a row to a database table.

-The user ID
-The date of the report

-The time of the report

-A description of how they are feeling

-A severity of the feeling (1-10)

Here are a few rows from the table. The app marketing team needs to understand their users better and asks the data analyst for various statistics. Which statistic CANNOT be calculated from the table of reports?

• The total number of reports from all users

• The user ID with the most number of reports

• The mean duration of the feeling

• The distribution of severity ratings across reports

It is your friend's 18^th birthday, and you need to use binary numbers for the candles on their cake. Your plan is to use green candles to mean "on" and gray candles to mean "off". What is the LEAST number of candles you need in order to represent their age?

Xiomara is a researcher studying the effect of carbon emissions from airplanes on global warming. She collects millions of data points tracking the path of airplanes and develops a program that analyzes the data. When she runs the program on a single company's airplanes, it takes an hour to complete, so she becomes concerned that it will take much too long to run on all of the airplane data. Her friend Dacari suggests using parallel computing to speed up the analysis of the airplane emission data. How would parallel computing speed up the analysis?

• Parallel computing will crowdsource the running of the program to volunteers on the Internet, utlizing the power of their machines instead.

• Parallel computing can distribute the work to multiple machines, so that each machine has more memory available for faster processing.

• Parallel computing will use a heuristic-based algorithm to compute the answer in less time.

• Parallel computing can run the program in parallel on subsets of the data, so that the total amount of time is less.

Consider a computer that uses 4 bits to represent nonnegative integers and uses all 4 bits to represent the value. Which of the following operations would result in integer overflow? There is at least one correct answer.

Stephanie is researching the friendliness of United States cities. To determine the friendliest and unfriendliest cities, she conducts a nation-wide survey. She then collects data about each of the cities, to try to understand what factors are related to a city's friendliness, and visualizes the data in scatter plots. This scatter plot (left) compares the population of cities to friendliness. This second scatter plot (right) compares each city's latitude to its friendliness. Which conclusion can Stephanie make from the data?

• When people move to a southern city, they become friendlier.

• When people move to a less populated city, they become friendlier.

• There is a positive correlation between latitude and friendliness.

• There is a stronger correlation between latitude and friendliness than between population and friendliness.

MIK is a character encoding scheme that can encode text written in Bulgarian. MIK uses one byte to encode each character. The binary data 101101111010000010110001 is an MIK encoding of a single Bulgarian word. How many characters are encoded in that binary data?

A programmer is designing a computer program for a weather application that will use a variety of data sources. They need 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 predicted millimetres of snowfall on a winter day for each city in the state of New York

• Thirty seconds of sound from a thunderstorm in Miami, Florida

• The daily time of sunrise and sunset in Detroit, Michigan

• Two years of weekly high temperatures for Houston, Texas

Tess is creating an alarm clock using a liquid-crystal display that looks like this one (left). Each digit will be 5 pixels wide and 7 pixels tall. She decides to save space by storing pixels for each digit using run-length encoding (RLE). RLE is a data compression technique that replaces "runs" (sequences of bits with the same value) with a number representing the length of the run. Here is the RLE for one of the digits (right). In her RLE scheme, the first number in each row represents a run of "off" pixels, the second number represents a run of "on" pixels, and subsequent numbers alternate between representing runs of "off" and "on" pixels. Which digit is represented by that encoding?