Quiz: Python Basics and Math Functions — 13 domande

1. What does Python display when it executes `print(2+5)`?

A. An error message

B. The number 7

C. The text `25`

D. The text `2+5`

Answer: (B)

Spiegazione

`print()` evaluates expressions before displaying them, so `2+5` is calculated and the output is 7. Writing `print("2+5")` would display the expression as text instead.

2. Which type of Python string can contain line breaks directly within its delimiters?

A. A numeric string

B. A triple-quoted string

C. A double-quoted string

D. A single-quoted string

Answer: (B)

Spiegazione

Triple-quoted strings can span multiple lines, whereas single- and double-quoted strings are generally used for single-line strings.

3. What value does `abs(-4)` return?

A. -4

B. 4

C. 0

D. An error because the number is negative

Answer: (B)

Spiegazione

The `abs()` function returns a number's absolute value, so `abs(-4)` returns 4 rather than preserving the original negative sign.

4. What does `pow(2,6)` calculate?

A. The sixth root of 2

B. 2 raised to the sixth power

C. The product of 2 and 6

D. The sum of 2 and 6

Answer: (B)

Spiegazione

`pow(a,b)` calculates a raised to the power of b. Therefore, `pow(2,6)` is 2⁶, which equals 64.

5. What does `round(3.14159, 2)` return?

A. 3.14

B. 3

C. 3.14159

D. 3.1

Answer: (A)

Spiegazione

The second argument of `round()` specifies the number of decimal places, so the value is rounded to two places as 3.14.

6. Which expression correctly calls the square-root function after executing `import math`?

A. `math->sqrt(25)`

B. `import.sqrt(25)`

C. `math.sqrt(25)`

D. `sqrt(25)`

Answer: (C)

Spiegazione

`import math` loads the module and requires its functions to be accessed with the `math.` prefix, making `math.sqrt(25)` correct. The unqualified form `sqrt(25)` requires a direct import.

7. Which statement correctly uses names imported with `from math import factorial, pi, log2`?

A. `factorial(5)`

B. `math->factorial(5)`

C. `module.factorial(5)`

D. `math.factorial(5)`

Answer: (A)

Spiegazione

A direct import places the selected names in the local namespace, so `factorial(5)` can be called without the `math.` prefix. Using `math.factorial(5)` corresponds to importing the module as `import math`.

8. How does an interpreter differ from a compiler when processing a Python program?

A. An interpreter processes and executes code line by line, while a compiler processes the program before execution

B. An interpreter displays code in an editor, while a compiler executes it in a terminal

C. An interpreter translates only mathematical expressions, while a compiler translates only text

D. An interpreter processes the entire program before execution, while a compiler runs code line by line

Answer: (A)

Spiegazione

An interpreter processes and executes code during execution, typically line by line. A compiler processes the program before it runs.

9. Which Visual Studio Code action runs a Python file without starting a debugging session?

A. Toggle Terminal using Ctrl+backtick

B. Run Without Debugging using Ctrl+F5

C. Format Document using Shift+Alt+F

D. Open File using Ctrl+O

Answer: (B)

Spiegazione

In Visual Studio Code, Run Without Debugging executes the Python file without launching a debugging session. Ctrl+F5 is the corresponding shortcut.

10. What is the primary purpose of a Python library?

A. To provide reusable functions and tools for a particular purpose

B. To display Python code without executing it

C. To convert all Python programs into web applications

D. To replace every individual function with a single command

Answer: (A)

Spiegazione

A Python library is a collection of ready-made, reusable code that provides functions or tools for a particular purpose. A single function is just one callable operation within or outside a library.

11. Which pairing correctly matches a Python library with its main application?

A. Matplotlib for machine learning and scikit-learn for visualization

B. NumPy for web development and Django for calculations

C. NumPy for calculations and Matplotlib for data visualization

D. Django for calculations and pandas for deep learning

Answer: (C)

Spiegazione

NumPy is associated with numerical calculations, while Matplotlib is used for data visualization. The other pairings assign libraries to applications they are not primarily associated with here.

12. Which formulas correctly calculate the circumference and area of a circle with radius 5?

A. C = 2π × 5 and A = π × 5²

B. C = π × 5 and A = 2π × 5²

C. C = π × 5² and A = 2π × 5

D. C = 4 × 5 and A = 5²

Answer: (A)

Spiegazione

A circle’s circumference uses C = 2πr, whereas its area uses A = πr². Substituting r = 5 gives the stated formulas.

13. A program needs to calculate both measurements of a square whose side length is 5 units. Which pair of expressions produces its perimeter and area, respectively?

A. 5² and 4 × 5

B. 4 × 5 and 5²

C. 5 + 5 and 4 × 5²

D. 4 + 5 and 5 × 5

Answer: (B)

Spiegazione

A square’s perimeter is found with 4s, giving 20 units, while its area is found with s², giving 25 square units. The formulas must not be reversed.