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JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 293 · 40 questions
TalentJR

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".

NameDateTime takenScore ___ / 40
  1. 1.⚡ Which JavaScript word runs code when true? (a) if (b) for (c) console.log() (d) alert()
  2. 2.⚡ Which JavaScript word repeats code? (a) for (b) let (c) console.log() (d) if
  3. 3.⚡ What number does this code print?
    let apples = 10;
    apples = apples + 7;
    apples = apples - 2;
    console.log(apples);
  4. 4.⚡ What does alert() show? (a) a pop-up box (b) a new tab (c) a picture (d) a table
  5. 5.⚡ What number does this code print?
    let a = 51;
    let b = 31;
    console.log(a + b);
  6. 6.⚡ Where does console.log() show its output? (a) on the printer (b) on the title bar (c) in the address bar (d) in the console
  7. 7.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 7;
    console.log(x + y);     (a) Error (b) 9 (c) 27
  8. 8.⚡ What number does this code print?
    let apples = 19;
    apples = apples + 7;
    apples = apples - 10;
    console.log(apples);
  9. 9.⚡ Which JavaScript word shows a pop-up box? (a) let (b) alert() (c) console.log() (d) for
  10. 10.⚡ What does this code show?
    let name = "Zoya";
    console.log("Hello, " + name + "!");     (a) Zoya (b) Hello, name! (c) Hello, Zoya! (d) name
  11. 11.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 5;
    console.log(x + y);     (a) Error (b) 25 (c) 7
  12. 12.⚡ What does this code show?
    let name = "Zoya";
    console.log("Hi, " + name + "!");     (a) name (b) Zoya (c) Hi, name! (d) Hi, Zoya!
  13. 13.⚡ Which JavaScript word writes in the console? (a) if (b) alert() (c) for (d) console.log()
  14. 14.⚡ What number does this code print?
    let a = 31;
    let b = 24;
    console.log(a + b);
  15. 15.⚡ What does this code show?
    let name = "Meera";
    console.log("Welcome, " + name + "!");     (a) Meera (b) Welcome, name! (c) Welcome, Meera! (d) name
  16. 16.⚡ What number does this code print?
    let a = 53;
    let b = 2;
    console.log(a + b);
  17. 17.⚡ Which word makes a new variable? (a) give (b) make (c) put (d) let
  18. 18.⚡ What does JavaScript add to a web page? (a) actions and changes (b) the domain name (c) only colours (d) the page title
  19. 19.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 9;
    console.log(x + y);     (a) Error (b) 29 (c) 11
  20. 20.⚡ What number does this code print?
    let a = 57;
    let b = 40;
    console.log(a - b);
  21. 21.⚡ What does this code show?
    let name = "Meera";
    alert("Welcome, " + name + "!");     (a) Welcome, Meera! (b) Meera (c) name (d) Welcome, name!
  22. 22.⚡ What number does this code print?
    let a = 38;
    let b = 34;
    console.log(a - b);
  23. 23.⚡ What number does this code print?
    let a = 41;
    let b = 16;
    console.log(a - b);
  24. 24.⚡ A JavaScript file usually ends with which extension? (a) .css (b) .jpg (c) .js (d) .html
  25. 25.⚡ What does this code show?
    let name = "Riya";
    alert("Well done, " + name + "!");     (a) Well done, Riya! (b) Riya (c) Well done, name! (d) name
  26. 26.⚡ What number does this code print?
    let a = 9;
    let b = 3;
    console.log(a * b);
  27. 27.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 9;
    console.log(x + y);     (a) 59 (b) 14 (c) Error
  28. 28.⚡ What number does this code print?
    let books = 14;
    books = books + 3;
    books = books - 2;
    console.log(books);
  29. 29.⚡ What number does this code print?
    let a = 4;
    let b = 9;
    console.log(a * b);
  30. 30.⚡ Which tag holds JavaScript in a page? (a) <style> (b) <js> (c) <code> (d) <script>
  31. 31.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 5;
    console.log(x + y);     (a) 8 (b) Error (c) 35
  32. 32.⚡ What number does this code print?
    let a = 53;
    let b = 16;
    console.log(a - b);
  33. 33.⚡ What number does this code print?
    let books = 14;
    books = books + 4;
    books = books - 2;
    console.log(books);
  34. 34.⚡ What number does this code print?
    let books = 27;
    books = books + 12;
    books = books - 4;
    console.log(books);
  35. 35.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 7;
    console.log(x + y);     (a) Error (b) 10 (c) 37
  36. 36.⚡ What does this code show?
    let name = "Kabir";
    console.log("Hello, " + name + "!");     (a) Hello, Kabir! (b) Hello, name! (c) name (d) Kabir
  37. 37.⚡ What number does this code print?
    let a = 7;
    let b = 2;
    console.log(a * b);
  38. 38.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 8;
    console.log(x + y);     (a) Error (b) 13 (c) 58
  39. 39.⚡ What number does this code print?
    let apples = 15;
    apples = apples + 12;
    apples = apples - 9;
    console.log(apples);
  40. 40.⚡ What does this code show?
    let name = "Kabir";
    alert("Hello, " + name + "!");     (a) Hello, name! (b) Kabir (c) Hello, Kabir! (d) name

Answer key

  1. if
  2. for
  3. 15
  4. a pop-up box
  5. 82
  6. in the console
  7. 27
  8. 16
  9. alert()
  10. Hello, Zoya!
  11. 25
  12. Hi, Zoya!
  13. console.log()
  14. 55
  15. Welcome, Meera!
  16. 55
  17. let
  18. actions and changes
  19. 29
  20. 17
  21. Welcome, Meera!
  22. 4
  23. 25
  24. .js
  25. Well done, Riya!
  26. 27
  27. 59
  28. 15
  29. 36
  30. <script>
  31. 35
  32. 37
  33. 16
  34. 35
  35. 37
  36. Hello, Kabir!
  37. 14
  38. 58
  39. 18
  40. Hello, Kabir!

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