unit 3 comp sci

unicode

a binary encoding system that can represent much more of the world's text than ASCII can (represents 65,536 different characters)

Morse Code

a code where letters are represented by combinations of long and short signals of light or sound.

data abstraction

help manage complexity in programs by giving a collection of data a name without referencing the specific details of the representation.

digital

how information is stored, accessed, transformed and used by computers

dichotomous

in which something can only be one thing or another (yes or no)

digital noise

irrelevant or meaningless data that has found its way into otherwise meaningful code.

alphanumeric

the characters that consists of uppercase and lowercase letters in addition to numerals 0-9.

There is a base 6 number system that uses symbols instead of numerals to represent different values. Below is the symbol that represents each numeral. ⤲ = 0↺ = 1➣ = 2⬳ = 3⤴ = 4⇶ = 5 Which of the following numbers written using this base 6 number system is equivalent to the base 10 number 147?

⤴ ⤲ ⬳

As movies and music have moved into the digital world, the legal protections that relate to them have had to continually evolve. Which of the following best describes how the legal landscape regarding the digital movies and music has changed?

The music and movie industries have chosen to protect their copyrights by filing lawsuits against people who share digital files without permission.

If our list called List is populated as [0, 1, 2, 3, 4], what happens if our code tries to access List [5] per the rules of the AP Computer Science Principles Reference Guide?

The output will be 4

continuous

unbroken, without interruption (analog)

variable-width encoding

using codes of different lengths to encode a character set for representation (example: Morse Code)

fixed-width encoding

using codes with a fixed width to encode a character set for representation (example: Baudot Code)

Using the table given below, determine the ASCII to binary code conversion for the word science.

01110011 01100011 01101001 01100101 01101110 01100011 01100101

What is the binary equivalent to the decimal number of 78?

1001110

Which of the following decimal values, when converted to binary (ignore leading zeros) have exactly 3 zeros in them? Select two answers.

20 & 50

ASCII is a common format for the representation of characters in writing code. How many characters can be represented in the standard ASCII encoding?

2^7

The following steps can be used to encode a string of text using Base64 encoding: 1. Convert the ASCII characters to their corresponding decimal value2. Convert the decimal values to their 8-bit equivalents3. Join all of the bits together to form one continuous string4. Split the combined string into groups of 6 bits5. From left to right, convert each group of 6 bits to their corresponding decimal values6. Convert those decimal values back to the corresponding Base64 values If I started with the three ASCII characters "CSP", how many Base64 values will I be left with at the end?

4

list

A list is an ordered sequence of elements. For example, [value1, value2, value3, ...] describes a list where value1 is the first element, value 2 is the second element, value 3 is the third element, and so on.

Which of the following statements about 32-bit binary values is NOT true?

All real numbers within a finite interval can be expressed by a 32-bit integer representation.

element

An element is an individual value in a list that is assigned a unique index.

A city engineer is tasked with studying vehicular traffic patterns throughout a large metropolitan area. He designs a number of small, remote devices that can be installed along streets throughout the city to sense and record the hundreds of cars that pass through each of the city's five busiest intersections during a 24-hour period. Every time a car trips the sensor in a device, it increments an internal, 5-bit counter that stores the number of cars that have passed through the intersection since the counter was last reset. Every 24 hours, each device transmits the 5-bit value stored in its counter back to a central server that collects the daily data from all of the devices throughout the city. After transmitting, the counter in each device is reset back to 0. Fortunately, the engineer's supervisor points out a flaw in the device's design and orders that the engineer modify the design specifications for this device before building and installing the sensors. Which of the following is most likely the design flaw in this scenario?

The counter is not capable of counting hundreds of cars without exceeding the limit of the five bits of storage.

Which of the following can be represented by a single binary digit?

The direction of travel for an elevator

Baudot Code

a binary code invented by Emile Baudot in 1870 that uses crosses and dots in order to encode 2^5 or 32 characters.

Which statements below are true about fixed and variable width encoding?

Variable width encoding must use extra bits to specify where characters start/end. & Fixed width encodings are typically longer than variable width encodings.

Which of the following questions cannot be easily answered using a binary set of answers?

Which is the best song new song from last year?

procedure

a group of blocks that are combined to perform a specific task.

string

a linear sequence of characters, words, or other data

data structure

a particular way of organizing and storing data such as an array, table, etc.

bit string

a sequence of bits that can be used to represent sets or to manipulate binary data.

substring

a subset of a string of alphanumeric fields or variables.

ASCII (American Standard Code for Information Interchange)

a table that outlines a common set of conventions established for converting between binary values and alphanumeric (represents 128 different characters)

mapping

associating each element of a given set with one or more elements of a second set.

data

characters, symbols or quantities on which operations are performed, stored and/or transmitted by a computer.

binary code

code represented with the two symbols of 1 and 0.

decimal

describes the base-10 number system. The most commonly used number system.

approximation

digital copies are only approximations of the natural object.

analog

non-digital signals or information represented by a continuously variable physical quantity such as spatial position or voltage.

real numbers

numbers approximated by floating-point representations that do not necessarily have infinite precision.

floating-point numbers

numbers where the decimal point can float because there is no fixed number of digits before and after the decimal point. AKA: real numbers

fixed-point numbers

numbers where the decimal point is always in the same place.

discrete

separate or divided (digital)

bits

the foundation for digital computing (1s and 0s) - short for binary digits

scientific notation

the mathematical representation of a decimal number in floating-point form. Examples: 4 x 10³ for 4,000, 4.002 x 10³x 10 for 4,002 or 2.345E6 for 2,345,000.

abstraction

the process of removing or suppressing details to create a manageable level of complexity.

exponential growth

the rate of growth that rapidly increases in proportion to the growing total number or size.

index value

the representation of the location of each item in a list.

state space

the space of potential possibilities