Unit 2

Question 1

2.1 - Variables and Assignments

What is a variable?

Answer 1

a named item that holds a value

Question 2

2.1 - Variables and Assignments

What are the two types of statements in programming?

Answer 2

declarative: create/assign variables
executable: instructs the computer to perform a task

Question 3

2.2 - Identifiers

What is an identifier?

Answer 3

the name of a variable

Question 4

2.2 - Identifiers

What are the requirements of an identifier?

Answer 4

starts with a letter, can use letters, underscores, and numbers, cannot contain spaces

Question 5

2.2 - Identifiers

IsnumPizzas the same as numpizzas?

Answer 5

No

Question 6

2.3 - Objects

What is an object?

Answer 6

something that represents a value, is mutable

Question 7

2.3 - Objects

What are the 3 properties of an object?

Answer 7

value, type, and identity

type: int, string, etc.
identity: describes object

value; number

Question 8

2.3 - Objects

What is mutability?

Answer 8

indicates if an object’s value can be changed

Question 9

2.4 - Numeric Types: Floating-Point

What is a floating-point number?

comonnly referred to as a float

Answer 9

a number that uses a decimal

ex. 3.14159

Question 10

2.4 - Numeric Types: Floating-Point

How do you use float()?

Answer 10

like int(), it converts numbers to a float

Question 11

2.4 - Numeric Types: Floating-Point

What is a floating-point literal?

Answer 11

a number with an unnecessary decimal

ex. 99 -> 99.0

Question 12

2.4 - Numeric Types: Floating-Point

How do you round a float?

within a print statement, to nearest 100th of a decimal

Answer 12

print(f'{myFloat:.2f}')

Question 13

2.5 - Arithmetic Expressions

What is an expression?

Answer 13

a combination of values that evaluates to a number

like 2 + 2

Question 14

2.5 - Arithmetic Expressions

What is a literal?

Answer 14

a specific value indepentent of an expression

2 + 2

Question 15

2.5 - Arithmetic Expressions

What type of precedence rules does Python use?

Answer 15

PEMDAS

parenthesis, exponents, multiplication, division, addition, subtraction

Question 16

2.6 - Python Expressions

What is a compound operator used for?

Answer 16

a quicker way to type variable = variable + 1, used as +=

Question 17

2.7 - Division and Modulo

What is floor division, and what symbol do you use for it

Answer 17

// divides a number, but rounds the answer downward

5 // 2 = 2

Question 18

2.7 - Division and Modulo

What is modulo, and what symbol do you use for it?

Answer 18

% finds the remainder of a division problem

4 % 2 = 0

Question 19

2.8 - Module Basics

What is a module?

also called a library

Answer 19

a file with pre-written Python code used in other programs; must be imported via dot notation

ex. universe.speed_of_light

Question 20

2.9 - Math Module

What does the math module do?

Answer 20

allows for more complex mathematical functions

ex. square roots

Question 21

2.9 - Math Module

What code from the math module would you use for powers? For square roots?

power - x^y
square root - √x

Answer 21

power: math.pow(x, y)
square root: math.sqrt(x)

Question 22

2.10 - Random Numbers

What code would you use to import the random numbers module?

Answer 22

import random

Question 23

2.10 - Random Numbers

Why is there no “true random” in computing?

Answer 23

randomization is based on a unique seed that creates a series of psuedo-random numbers

Question 24

2.10 - Random Numbers

What is the difference between inclusive and exclusive numbers?

Answer 24

inclusive - includes the number in range
exclusive - excludes the number in range