ExamAdept

What is the value of x after executing the following code:

x = [1, 2, 3]
y = x
x[0] = 4
print(y)

A:

[4, 2, 3]

B:

[1, 2, 3]

C:

[4, 2, 2]

D:

An error is raised

Answer: A

In Python, when a list is assigned to a variable, the variable holds a reference to the list rather than a copy of the list. In this case, the variable y holds a reference to the same list as x. When x[0] is changed to 4, the list is modified and both x and y reflect this change.

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Which of the following is true about Python variable names?

A:

Variable names are case-sensitive

B:

Variable names cannot be longer than 32 characters

C:

Variable names can contain special characters like @ or $

D:

None of the above

Answer: A

In Python, variable names are case-sensitive, which means that my_variable and My_Variable are two different variable names. Variable names can be any length and can contain letters, numbers, and underscores, but cannot begin with a number and cannot contain special characters like @ or $.

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What is the output of the following code:

x = 10; y = 3
z = x % y
print(z)

A:

1

B:

3

C:

9

D:

Results an error due to the semicolon ( ; ) .

Answer: A

In Python, the % operator is used to calculate the remainder of a division operation. In this case, 10 divided by 3 has a remainder of 1, which is stored in the variable z and printed to the console.

Python does not usually use explicit line-ending characters; the parser can almost always figure out where a statement ends from the positioning of newlines. However, Python's syntax allows you to use a semicolon to end a statement instead, which allows you to place multiple statements on a single line.

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Which of the following is a valid way to concatenate two strings?

A:

str1 . str2

B:

str1 + str2

C:

str1 * str2

D:

str1 | str2

Answer: B

In Python, the + operator is used to concatenate two strings. For example, "Hello, " + "ExamAdept" would result in the string "Hello, ExamAdept".

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What is the value of x after executing the following code?

x = 5
x = "ExamAdept"

A:

5

B:

"ExamAdept"

C:

"5"

D:

An error is raised

Answer: B

In Python, variables can be assigned to different data types. When a variable is assigned to a new value, the old value is overwritten with the new value. In this case, the variable x is first assigned to the integer 5, but is then reassigned to the string "ExamAdept".

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Questions for: Variables