Question 1

Which statements accurately describe Python lists? (Select all)

• Lists are mutable. ✅

• Lists are immutable. ❌

• Lists can contain sequences of elements of any data type. ✅

• Lists can be indexed and sliced. ✅

Explanation:
Lists can be changed, store mixed types, and support indexing/slicing.

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Question 2

If ‘Houston’ is the third element, it is at index 2. The correct code is:

• cities.pop(1) ❌

• cities.pop(4) ❌

• cities.pop(3) ❌

• cities.pop(2) ✅

Explanation:
List indexing starts at 0 → third element = index 2.

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Question 3

What types of data can tuples contain? (Select all)

• Modules ❌

• Strings ✅

• Floats ✅

• Integers ✅

Explanation:
Tuples can hold any data type — just like lists — but are immutable.

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Question 4

Character used to instantiate a dictionary:

• ( ) ❌

• < > ❌

• ❌

• { } ✅

Explanation:
Curly braces { } are used for dictionaries.

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Question 5

Retrieve both keys and values:

• employees.keys() ❌ (keys only)

• items.employees() ❌

• employees.items() ✅

• keys.employees() ❌

Explanation:
.items() returns (key, value) pairs.

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Question 6

Find elements present in A but not in B:

• intersection() ❌

• symmetric_difference() ❌

• union() ❌

• difference() ✅

Explanation:
A.difference(B) returns items only in A.

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Question 7

Fill in the blank: In Python, _____ contain collections of functions and variables.

• keywords ❌

• logical operators ❌

• comparators ❌

• modules ✅

Explanation:
Modules package reusable functions and variables.

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Question 8

A _____ NumPy array can be created from a list of lists of equal length.

• two-dimensional ✅

• one-dimensional ❌

• four-dimensional ❌

• three-dimensional ❌

Explanation:
A list of lists creates a 2D array (rows × columns).

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Question 9

Mean of the Price column:

• sales.mean().[Price] ❌

• sales[‘Price’].mean() ✅

• sales = mean().Price ❌

• sales.(Price).mean() ❌

Explanation:
Access the column with sales['Price'] then call .mean().

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Question 10

Difference between iloc[] and loc[]:

• iloc merges… ❌

• iloc selects by name… ❌

• iloc selects by index; loc selects by name. ✅

• iloc merges… ❌

Explanation:

• iloc → integer positions

• loc → label names

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Question 11

Join that includes all keys from both dataframes:

• Left join ❌

• Inner join ❌

• Outer join ✅

• Right join ❌

Explanation:
Outer join keeps everything, filling in missing values with NaN.

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🧾 Summary Table

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