AP-CSP

Which of the following best describes a challenge involved in using a parallel computing solution?

A parallel computing solution may not be appropriate for an algorithm in which each step requires the output from the preceding steps.

Which of the following is a true statement about the use of public key encryption in transmitting messages?

Public key encryption enables parties to initiate secure communication through an open medium, such as the Internet, in which there might be eavesdroppers.

Which of the following best explains the relationship between the Internet and the World Wide Web?

The Internet is a network of interconnected networks, and the World Wide Web is a system of linked pages, programs, and files that are accessed via the Internet.

Which of the following is an example of an attack using a rogue access point?

An unauthorized individual gains the ability to view network traffic by connecting to a network router that uses weak or no security measures.

A code segment is intended to transform the list utensils so that the last element of the list is moved to the beginning of the list. For example, if utensils initially contains ["fork", "spoon", "tongs", "spatula", "whisk"], it should contain ["whisk", "fork", "spoon", "tongs", "spatula"] after executing the code segment. Which of the following code segments transforms the list as intended?

len ← LENGTH (utensils) temp ← utensils [len] REMOVE (utensils, len) APPEND (utensils, temp)

A video-streaming Web site keeps count of the number of times each video has been played since it was first added to the site. The count is updated each time a video is played and is displayed next to each video to show its popularity. At one time, the count for the most popular video was about two million. Sometime later, the same video displayed a seven-digit negative number as its count, while the counts for the other videos displayed correctly. Which of the following is the most likely explanation for the error?

The count for the video became larger than the maximum value allowed by the data type used to store the count.

A sorted list of numbers contains 128 elements. Which of the following is closest to the maximum number of list elements that can be examined when performing a binary search for a value in the list?

8

Which of the following best exemplifies the use of keylogging to gain unauthorized access to a computer system?

A user unintentionally installs a program on their computer that records all user input and forwards it to another computer. A few weeks later, someone else is able to access the user's computer using the recorded data.

In the following procedure, the parameter age represents a person's age. The procedure is intended to return the name of the age group associated with age. People who are under 18 are considered minors, people who are 65 and older are considered senior citizens, and all other people are considered adults. The procedure does not work as intended. Line 1: PROCEDURE ageGroup(age) Line 2: { Line 3: result ← "adult" Line 4: IF(age ≥ 65) Line 5: { Line 6: result ← "senior citizen" Line 7: } Line 8: RETURN(result) Line 9: Line 10: result ← "adult" Line 11: IF(age < 18) Line 12: { Line 13: result ← "minor" Line 14: } Line 15: RETURN(result) Line 16: } Removing which two lines of code will cause the procedure to work as intended? Select TWO answers

Line 8 Line 10

A list of numbers has n elements, indexed from 1 to n. The following algorithm is intended to display true if the value target appears in the list more than once and to display false otherwise. The algorithm uses the variables position and count. Steps 4 and 5 are missing. Step 1: Set count to 0 and position to 1. Step 2: If the value of the element at index position is equal to target, increase the value of count by 1. Step 3: Increase the value of position by 1. Step 4: (missing step) Step 5: (missing step) Which of the following could be used to replace steps 4 and 5 so that the algorithm works as intended?

Step 4: Repeat steps 2 and 3 until the value of position is greater than n. Step 5: If count is greater than or equal to 2, display true. Otherwise, display false.

Which of the following best explains the ability to solve problems algorithmically?

There exist some problems that cannot be solved algorithmically using any computer.

The following code segment is intended to remove all duplicate elements in the list myList. The procedure does not work as intended. j \leftarrow← LENGTH (myList) REPEAT UNTIL (j = 1) { IF (myList [j] = myList [j - 1]) { REMOVE (myList, j) } j j - 1 } For which of the following contents of myList will the procedure NOT produce the intended results? Select TWO answers.

[10, 10, 20, 20, 10, 10] [30, 50, 40, 10, 20, 40]

The question below uses a robot in a grid of squares. The robot is represented as a triangle, which is initially in the center square and facing toward the top of the grid. The following code segment is used to move the robot in the grid. Count \leftarrow← 1 REPEAT 4 TIMES { REPEAT count TIMES { MOVE_FORWARD () } ROTATE_LEFT () count count + 1 } Which of the following code segments will move the robot from the center square along the same path as the code segment above?

count ← 0 REPEAT 4 TIMES { count count + 1 REPEAT count TIMES { MOVE_FOWARD () } ROTATE_LEFT () }

Consider the following procedure. Procedure Call drawLine (x1, y1, x2, y2) Explanation Draws a line segment on a coordinate grid with endpoints at coordinates (x1, y1) and (x2, y2) The drawLine procedure is to be used to draw the following figure on a coordinate grid.

xVal ← 1 yVal ← 0 len ← 1 REPEAT 5 TIMES { drawLine(xVal, yVal, xVal, yVal + len) xVal ← xVal + 1 len ← len + 1 }

The following table shows the value of expression based on the values of input1 and input2. Value of input1 true true false false Value of input2 true false true false Value of expression false true true true Which of the following expressions are equivalent to the value of expression as shown in the table? Select TWO answers.

(NOT input1) OR (NOT input2) NOT (input1 AND input2)

RunRoutr is a fitness tracking application for smartphones that creates suggested running routes so that users can run with each other. Upon downloading the application, each user creates a username, a personal profile, and a contact list of friends who also use the application. The application uses the smartphone's GPS unit to track a user's location, running speed, and distance traveled. Users can use the application to review information and statistics about their previous runs . At the beginning of a run, users indicate the distance they want to run from their current location, and the application suggests a running route. Once a user accepts a suggested route, the application shares the suggested route with other compatible users in the area so that they can run together. Users are considered compatible if they are on each other's contact lists or if they typically run at similar speeds. A basic RunRoutr account is free, but it displays advertisements that are targeted to individual users based on data collected by the application. For example, if a user's running route begins or ends near a particular store, the application may display an advertisement for that store. Users have the ability to pay a monthly fee for a premium account, which removes advertisements from the application. Which of the following is most likely to be a benefit to users of the application?

Users of the application may see health benefits as a result of the application encouraging them to exercise with each other.

The following procedures are available for string manipulation. Procedure Call substring(str, start, end) concat(str1, str2) len(str) Explanation Returns a substring of consecutive characters of str starting with the character at position start and ending with the character at position end. The first character of str is considered position 1. For example, substring("delivery", 3, 6) returns "live". Returns a single string consisting of str1 followed by str2. For example, concat("key", "board") returns "keyboard". Returns the number of characters in str. For example, len("key") returns 3. A programmer wants to create a new string by removing the character in position n of the string oldStr. For example, if oldStr is "best" and n is 3, then the new string should be "bet". Assume that 1 < n < len(oldStr). Which of the following code segments can be used to create the desired new string and store it in newStr ? Select TWO answers.

left ←\leftarrow← substring (oldStr, 1, n - 1) right ←\leftarrow← substring (oldStr, n + 1, len(oldStr)) newStr ←\leftarrow← concat (left, right) newStr ←\leftarrow← substring (oldStr, 1, n - 1) newStr ←\leftarrow← concat (newStr, substring (oldStr, n + 1, len (oldStr)))

A store uses binary numbers to assign a unique binary sequence to each item in its inventory. What is the minimum number of bits required for each binary sequence if the store has between 75 and 100 items in its inventory?

7

A binary number is to be transformed by appending three 0s to the end of the number. For example, 11101 is transformed to 11101000. Which of the following correctly describes the relationship between the transformed number and the original number?

The transformed number is 8 times the value of the original number.

Each student at a school has a unique student ID number. A teacher has the following spreadsheets available. Spreadsheet I contains information on all students at the school. For each entry in this spreadsheet, the student name, the student ID, and the student's grade point average are included. Spreadsheet II contains information on only students who play at least one sport. For each entry in this spreadsheet, the student ID and the names of the sports the student plays are included. Spreadsheet III contains information on only students whose grade point average is greater than 3.5. For each entry in this spreadsheet, the student name and the student ID are included. Spreadsheet IV contains information on only students who play more than one sport. For each entry in this spreadsheet, the student name and the student ID are included. The teacher wants to determine whether students who play a sport are more or less likely to have higher grade point averages than students who do not play any sports. Which of the following pairs of spreadsheets can be combined and analyzed to determine the desired information?

Spreadsheets I and II