JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 501 · 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.⚡ What does this code show?
   let name = "Kabir";
   alert("Hello, " + name + "!"); (a) Hello, Kabir! (b) Kabir (c) name (d) Hello, name!
2. 2.⚡ Which JavaScript word writes in the console? (a) alert() (b) let (c) if (d) console.log()
3. 3.⚡ What does this code print? (Look at the quotes!)
   let x = "6";
   let y = 8;
   console.log(x + y); (a) 68 (b) Error (c) 14
4. 4.⚡ Which JavaScript word makes a new variable? (a) alert() (b) for (c) if (d) let
5. 5.⚡ Which word makes a new variable? (a) let (b) make (c) put (d) give
6. 6.⚡ What does this code print? (Look at the quotes!)
   let x = "9";
   let y = 5;
   console.log(x + y); (a) 95 (b) Error (c) 14
7. 7.⚡ Where does console.log() show its output? (a) on the printer (b) in the address bar (c) in the console (d) on the title bar
8. 8.⚡ What number does this code print?
   let a = 51;
   let b = 21;
   console.log(a + b);
9. 9.⚡ What number does this code print?
   let a = 19;
   let b = 35;
   console.log(a + b);
10. 10.⚡ A JavaScript file usually ends with which extension? (a) .html (b) .css (c) .jpg (d) .js
11. 11.⚡ What number does this code print?
    let a = 8;
    let b = 3;
    console.log(a + b);
12. 12.⚡ Which JavaScript word repeats code? (a) if (b) let (c) for (d) alert()
13. 13.⚡ What does this code print? (Look at the quotes!)
    let x = "7";
    let y = 1;
    console.log(x + y); (a) 8 (b) 71 (c) Error
14. 14.⚡ Which tag holds JavaScript in a page? (a) <js> (b) <style> (c) <script> (d) <code>
15. 15.⚡ What number does this code print?
    let runs = 10;
    runs = runs + 15;
    runs = runs - 23;
    console.log(runs);
16. 16.⚡ Which JavaScript word runs code when true? (a) console.log() (b) for (c) alert() (d) if
17. 17.⚡ What number does this code print?
    let books = 13;
    books = books + 7;
    books = books - 13;
    console.log(books);
18. 18.⚡ What number does this code print?
    let a = 8;
    let b = 9;
    console.log(a + b);
19. 19.⚡ What number does this code print?
    let a = 40;
    let b = 38;
    console.log(a - b);
20. 20.⚡ Which JavaScript word shows a pop-up box? (a) alert() (b) for (c) if (d) console.log()
21. 21.⚡ What number does this code print?
    let a = 2;
    let b = 5;
    console.log(a * b);
22. 22.⚡ What does JavaScript add to a web page? (a) the domain name (b) actions and changes (c) only colours (d) the page title
23. 23.⚡ What number does this code print?
    let a = 36;
    let b = 5;
    console.log(a - b);
24. 24.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 9;
    console.log(x + y); (a) Error (b) 89 (c) 17
25. 25.⚡ What number does this code print?
    let score = 14;
    score = score + 9;
    score = score - 3;
    console.log(score);
26. 26.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 6;
    console.log(x + y); (a) 56 (b) Error (c) 11
27. 27.⚡ What number does this code print?
    let a = 20;
    let b = 40;
    console.log(a + b);
28. 28.⚡ What number does this code print?
    let a = 60;
    let b = 22;
    console.log(a - b);
29. 29.⚡ What number does this code print?
    let a = 22;
    let b = 34;
    console.log(a + b);
30. 30.⚡ What number does this code print?
    let a = 27;
    let b = 36;
    console.log(a + b);
31. 31.⚡ What number does this code print?
    let a = 46;
    let b = 31;
    console.log(a + b);
32. 32.⚡ What number does this code print?
    let a = 11;
    let b = 13;
    console.log(a + b);
33. 33.⚡ What does this code show?
    let name = "Riya";
    alert("Hi, " + name + "!"); (a) Hi, name! (b) Riya (c) name (d) Hi, Riya!
34. 34.⚡ What number does this code print?
    let a = 15;
    let b = 27;
    console.log(a + b);
35. 35.⚡ What does this code show?
    let name = "Arjun";
    console.log("Hi, " + name + "!"); (a) Hi, Arjun! (b) Arjun (c) name (d) Hi, name!
36. 36.⚡ What does this code show?
    let name = "Riya";
    alert("Hello, " + name + "!"); (a) Hello, Riya! (b) Riya (c) name (d) Hello, name!
37. 37.⚡ What number does this code print?
    let a = 18;
    let b = 8;
    console.log(a - b);
38. 38.⚡ What does this code show?
    let name = "Kabir";
    console.log("Welcome, " + name + "!"); (a) Welcome, Kabir! (b) name (c) Welcome, name! (d) Kabir
39. 39.⚡ What does this code show?
    let name = "Meera";
    alert("Well done, " + name + "!"); (a) Well done, name! (b) Well done, Meera! (c) Meera (d) name
40. 40.⚡ What number does this code print?
    let marks = 9;
    marks = marks + 19;
    marks = marks - 14;
    console.log(marks);

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