PCAP Strings Practice Test 6 — 15 Questions

Question 1

A programmer has a string 'apple,banana,orange' and wants to get a list ['apple', 'banana', 'orange']. Which method should be used?

Accepted Answer

s.split(','). `s.split(',')` splits the string `'apple,banana,orange'` at each comma delimiter, returning a list of substrings: `['apple', 'banana', 'orange']`. This method is designed to break a string into a list based on a specified separator, making it the exact tool for this task.

Answer

s.splitlines()

Answer

s.partition(',')

Answer

s.join(',')

Question 2

A developer wants to check if a string 'example.txt' ends with '.txt'. Which expression returns True?

Accepted Answer

'example.txt'.endswith('.txt'). The `endswith()` method is specifically designed to check if a string ends with a given suffix. In this case, `'example.txt'.endswith('.txt')` returns `True` because the string ends with the substring '.txt'.

Answer

'example.txt'.startswith('.txt')

Answer

'example.txt'.find('.txt')

Answer

'example.txt'.rsplit('.',1)

Question 3

A developer needs to format a floating-point number 123.456789 with exactly 2 decimal places and a width of 10 characters, right-aligned. Which format specifier accomplishes this?

Accepted Answer

:10.2f. The format specifier `:10.2f` combines a total width of 10 characters with exactly 2 decimal places for a floating-point number, right-aligned by default. The `f` type ensures fixed-point notation, and the width of 10 includes the decimal point and digits, padding with spaces on the left.

Answer

:.2f

Answer

:10.2g

Answer

:10.2e

Question 4

Which TWO of the following string methods return a boolean value (True or False)?

Accepted Answer

str.startswith(). Both `str.startswith()` and `str.isdigit()` return a boolean value (`True` or `False`) because they are designed for conditional checks. `str.startswith()` checks if the string starts with a given prefix, while `str.isdigit()` checks if all characters in the string are digits. In contrast, `str.upper()` returns a new string, `str.split()` returns a list, and `str.find()` returns an integer index. Therefore, options C and D are the correct answers.

Answer

str.upper()

Answer

str.split()

Answer

str.find()

Question 5

Which THREE of the following are valid ways to create a string in Python?

Accepted Answer

'Hello'. In Python, valid string literals can be enclosed in single quotes, double quotes, triple single quotes, or triple double quotes. Formatted string literals (f-strings) are also valid. Option A is invalid because it uses mismatched quote characters: it opens with a single quote but closes with a double quote. Option B uses consistent single quotes. Option C is an f-string. Option D uses backticks, which are not valid Python string delimiters. Option E uses triple single quotes, which are valid for multi-line strings.

Answer

'Hello"

Answer

`Hello`

Question 6

Which TWO of the following operations can be performed on a string?

Accepted Answer

Slicing with [::]. String slicing with the syntax `[start:stop:step]` (e.g., `[::]`) is a built-in operation for strings in Python, allowing extraction of substrings. Option E is correct because the `+` operator performs string concatenation, creating a new string by joining two strings together.

Answer

Extend with .extend()

Answer

Append with .append()

Answer

Pop with .pop()

Question 7

A developer is writing a function that validates a user input string to ensure it contains only ASCII digits (0-9) for a numeric ID field. Which method should be used to check the string?

Accepted Answer

isdecimal(). The isdecimal() method returns True if all characters are decimal digit characters, i.e., characters used to form numbers in base 10 (including 0-9 and other Unicode decimal digits like Arabic-Indic digits). It excludes superscripts, subscripts, and other numeric characters that isdigit() or isnumeric() would accept. This makes it the best choice among the given options for validating a string that should contain only decimal digit characters. Note that for truly ASCII-only validation, additional checks (e.g., isascii()) would be needed. The PCAP exam often tests the differences between isdecimal(), isdigit(), and isnumeric(), expecting candidates to know that isdigit() returns True for superscript digits (like '²'), while isdecimal() does not, making isdecimal() more appropriate for ensuring decimal digits.

Answer

isnumeric()

Answer

isdigit()

Answer

isalpha()

Question 8

A developer gets the following error while running a Python script: 'TypeError: not all arguments converted during string formatting'. The relevant code is: print('Progress: %d%%' % (percent)). The variable 'percent' is an integer. What is the most likely cause and fix?

Accepted Answer

The percent sign must be escaped as '%%' to be treated as a literal.. In Python's %-formatting, '%%' is the escape sequence that produces a single literal '%' without consuming an argument. The format string 'Progress: %d%%' contains two items: '%d' consumes one integer argument, and '%%' outputs '%'. Since exactly one argument (percent) is provided, all arguments are converted and no TypeError occurs. The error 'not all arguments converted during string formatting' would only happen if there were additional unconverted arguments or an unterminated/unpaired '%' in the format string. Thus the code as given is correct; the reported error must come from a different format string.

Answer

There is a mismatch between the number of format specifiers and the number of arguments; add another argument.

Answer

Convert the integer to a string using str(percent) before formatting.

Answer

Switch from %-formatting to an f-string: f'Progress: {percent}%'

Question 9

Which TWO statements about Python strings are correct? (Choose exactly 2 correct answers.)

Accepted Answer

Strings are immutable; operations like concatenation produce a new string.. Python strings are immutable, meaning once a string object is created, its content cannot be changed. Any operation that appears to modify a string, such as concatenation with the + operator, actually creates a brand-new string object in memory, leaving the original unchanged.

Answer

Strings are mutable; you can change individual characters via indexing.

Answer

Strings have an .append() method to add characters at the end.

Answer

You can assign a new character to a position in a string using indexing: s[0] = 'a'.

Question 10

A developer wants to check if a string 'racecar' is a palindrome by comparing it to its reverse. Which code completes the task correctly?

Accepted Answer

s[::-1] == s. The slicing syntax `s[::-1]` creates a reversed copy of the string `s`, and comparing it to `s` with `==` checks if the string reads the same forwards and backwards, which is the definition of a palindrome. For the string 'racecar', `s[::-1]` returns 'racecar', so the comparison is `True`.

Answer

reversed(s) == s

Answer

s[::1] == s

Answer

s.reverse() == s

Question 11

Given the code: s = 'Python'; t = s; s = s + '3.0'. What is the value of t after these lines execute?

Accepted Answer

'Python'. Strings in Python are immutable. The assignment `t = s` makes `t` reference the same string object as `s`. When `s = s + '3.0'` executes, a new string object `'Python3.0'` is created and bound to `s`, while `t` still references the original string `'Python'`. Thus, `t` remains `'Python'`.

Answer

It raises an error because s was reassigned.

Answer

''

Answer

'Python3.0'

Question 12

What will the above code output?

Accepted Answer

Index out of range. The code attempts to access an index that is outside the valid range of the string. In Python, strings are zero-indexed, so for a string of length n, valid indices are 0 to n-1. Accessing an index equal to or greater than the length raises an IndexError, which is exactly what 'Index out of range' describes.

Answer

The program runs without output.

Answer

The program crashes with an unhandled IndexError.

Answer

ValueError is raised.

Question 13

What is the output of the code in the exhibit?

Accepted Answer

Alice is 30 years old.. The code uses an f-string which substitutes the values of the variables `name` and `age` into the string. Evaluating the expression results in 'Alice is 30 years old.', matching option B. Option A shows the literal braces, option C displays the variable names instead of their values, and option D reverses the order of the variables.

Answer

{name} is {age} years old.

Answer

name is age years old.

Answer

30 is Alice years old.

Question 14

Given the code above, what is printed? Note: each backslash is a single character.

Accepted Answer

23. The string "C:\Users\John\Documents" uses double backslashes to represent literal backslashes. Each double backslash `\` is a single backslash character. Counting all characters: C, :, \, U, s, e, r, s, \, J, o, h, n, \, D, o, c, u, m, e, n, t, s = 23 characters. Thus, the length is 23.

Answer

21

Answer

22

Answer

24

Question 15

Which THREE of the following string methods return a boolean value (True or False)? (Choose exactly 3 correct answers.)

Accepted Answer

isspace(). The `isspace()` method returns `True` if all characters in the string are whitespace characters (e.g., space, tab, newline) and the string is non-empty; otherwise, it returns `False`. This is a boolean-returning method that checks a specific character property, making option A correct.

Answer

replace()

Answer

find()