JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 828 · 40 questions

Code tip (Line by line): let x = 5; makes a variable x holding 5; x = x + 2; changes it to 7. console.log(…) writes in the console; alert(…) shows a pop-up box. Text in quotes + anything = joined text: "5" + 3 → "53".

1. 1.⚡ A JavaScript file usually ends with which extension? (a) .css (b) .html (c) .jpg (d) .js
2. 2.⚡ Which JavaScript word repeats code? (a) console.log() (b) if (c) for (d) alert()
3. 3.⚡ What does this code print? (Look at the quotes!)
   let x = "7";
   let y = 6;
   console.log(x + y); (a) Error (b) 76 (c) 13
4. 4.⚡ Which tag holds JavaScript in a page? (a) <style> (b) <code> (c) <js> (d) <script>
5. 5.⚡ What does this code print? (Look at the quotes!)
   let x = "8";
   let y = 3;
   console.log(x + y); (a) 11 (b) Error (c) 83
6. 6.⚡ Which JavaScript word writes in the console? (a) for (b) console.log() (c) alert() (d) if
7. 7.⚡ What number does this code print?
   let marks = 21;
   marks = marks + 20;
   marks = marks - 34;
   console.log(marks);
8. 8.⚡ Where does console.log() show its output? (a) in the address bar (b) in the console (c) on the title bar (d) on the printer
9. 9.⚡ What number does this code print?
   let apples = 11;
   apples = apples + 2;
   apples = apples - 4;
   console.log(apples);
10. 10.⚡ Which JavaScript word runs code when true? (a) let (b) for (c) console.log() (d) if
11. 11.⚡ What does this code show?
    let name = "Meera";
    alert("Hi, " + name + "!"); (a) Meera (b) Hi, Meera! (c) Hi, name! (d) name
12. 12.⚡ What does this code show?
    let name = "Riya";
    console.log("Hi, " + name + "!"); (a) Hi, name! (b) name (c) Riya (d) Hi, Riya!
13. 13.⚡ What number does this code print?
    let a = 12;
    let b = 2;
    console.log(a * b);
14. 14.⚡ What number does this code print?
    let a = 5;
    let b = 8;
    console.log(a * b);
15. 15.⚡ What does this code show?
    let name = "Kabir";
    console.log("Hello, " + name + "!"); (a) Hello, name! (b) Kabir (c) name (d) Hello, Kabir!
16. 16.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 8;
    console.log(x + y); (a) Error (b) 10 (c) 28
17. 17.⚡ What does JavaScript add to a web page? (a) the page title (b) the domain name (c) actions and changes (d) only colours
18. 18.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 4;
    console.log(x + y); (a) 12 (b) Error (c) 84
19. 19.⚡ What number does this code print?
    let a = 19;
    let b = 5;
    console.log(a + b);
20. 20.⚡ What number does this code print?
    let marks = 26;
    marks = marks + 6;
    marks = marks - 14;
    console.log(marks);
21. 21.⚡ Which JavaScript word shows a pop-up box? (a) console.log() (b) let (c) alert() (d) for
22. 22.⚡ Which JavaScript word makes a new variable? (a) console.log() (b) let (c) for (d) if
23. 23.⚡ What number does this code print?
    let a = 5;
    let b = 7;
    console.log(a * b);
24. 24.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 7;
    console.log(x + y); (a) Error (b) 12 (c) 57
25. 25.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 5;
    console.log(x + y); (a) 65 (b) Error (c) 11
26. 26.⚡ Which word makes a new variable? (a) give (b) let (c) put (d) make
27. 27.⚡ What number does this code print?
    let a = 36;
    let b = 10;
    console.log(a - b);
28. 28.⚡ What does this code show?
    let name = "Arjun";
    console.log("Hi, " + name + "!"); (a) Hi, name! (b) Arjun (c) Hi, Arjun! (d) name
29. 29.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 1;
    console.log(x + y); (a) Error (b) 51 (c) 6
30. 30.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 8;
    console.log(x + y); (a) Error (b) 17 (c) 98
31. 31.⚡ What number does this code print?
    let a = 27;
    let b = 19;
    console.log(a - b);
32. 32.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 8;
    console.log(x + y); (a) 12 (b) 48 (c) Error
33. 33.⚡ What number does this code print?
    let a = 30;
    let b = 3;
    console.log(a - b);
34. 34.⚡ What does alert() show? (a) a picture (b) a pop-up box (c) a table (d) a new tab
35. 35.⚡ What does this code show?
    let name = "Aman";
    console.log("Well done, " + name + "!"); (a) Well done, name! (b) name (c) Aman (d) Well done, Aman!
36. 36.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 7;
    console.log(x + y); (a) 37 (b) 10 (c) Error
37. 37.⚡ What does this code show?
    let name = "Meera";
    console.log("Hi, " + name + "!"); (a) Hi, name! (b) name (c) Meera (d) Hi, Meera!
38. 38.⚡ What number does this code print?
    let books = 12;
    books = books + 16;
    books = books - 9;
    console.log(books);
39. 39.⚡ What number does this code print?
    let coins = 6;
    coins = coins + 12;
    coins = coins - 8;
    console.log(coins);
40. 40.⚡ What number does this code print?
    let a = 10;
    let b = 12;
    console.log(a * b);

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