JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 584 · 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.⚡ Which JavaScript word shows a pop-up box? (a) console.log() (b) let (c) alert() (d) if
2. 2.⚡ Which JavaScript word runs code when true? (a) console.log() (b) if (c) alert() (d) let
3. 3.⚡ What does this code print? (Look at the quotes!)
   let x = "3";
   let y = 9;
   console.log(x + y); (a) 12 (b) Error (c) 39
4. 4.⚡ What does this code show?
   let name = "Arjun";
   alert("Hi, " + name + "!"); (a) name (b) Hi, name! (c) Hi, Arjun! (d) Arjun
5. 5.⚡ What number does this code print?
   let a = 15;
   let b = 31;
   console.log(a + b);
6. 6.⚡ What does this code show?
   let name = "Riya";
   console.log("Well done, " + name + "!"); (a) Riya (b) Well done, Riya! (c) Well done, name! (d) name
7. 7.⚡ What number does this code print?
   let books = 30;
   books = books + 18;
   books = books - 38;
   console.log(books);
8. 8.⚡ Which JavaScript word makes a new variable? (a) for (b) let (c) if (d) alert()
9. 9.⚡ Which JavaScript word repeats code? (a) console.log() (b) if (c) for (d) alert()
10. 10.⚡ What does this code show?
    let name = "Riya";
    alert("Hello, " + name + "!"); (a) Hello, Riya! (b) Riya (c) name (d) Hello, name!
11. 11.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 2;
    console.log(x + y); (a) 22 (b) 4 (c) Error
12. 12.⚡ A JavaScript file usually ends with which extension? (a) .jpg (b) .css (c) .js (d) .html
13. 13.⚡ What does this code show?
    let name = "Kabir";
    console.log("Welcome, " + name + "!"); (a) name (b) Kabir (c) Welcome, Kabir! (d) Welcome, name!
14. 14.⚡ What number does this code print?
    let a = 38;
    let b = 18;
    console.log(a + b);
15. 15.⚡ Which JavaScript word writes in the console? (a) console.log() (b) let (c) alert() (d) for
16. 16.⚡ What does alert() show? (a) a new tab (b) a picture (c) a table (d) a pop-up box
17. 17.⚡ What number does this code print?
    let a = 9;
    let b = 11;
    console.log(a * b);
18. 18.⚡ What does this code show?
    let name = "Arjun";
    console.log("Well done, " + name + "!"); (a) Well done, Arjun! (b) Well done, name! (c) Arjun (d) name
19. 19.⚡ What does JavaScript add to a web page? (a) the page title (b) only colours (c) the domain name (d) actions and changes
20. 20.⚡ What number does this code print?
    let a = 60;
    let b = 37;
    console.log(a - b);
21. 21.⚡ Which word makes a new variable? (a) make (b) put (c) let (d) give
22. 22.⚡ What does this code show?
    let name = "Zoya";
    alert("Welcome, " + name + "!"); (a) Zoya (b) Welcome, Zoya! (c) name (d) Welcome, name!
23. 23.⚡ What number does this code print?
    let a = 10;
    let b = 9;
    console.log(a * b);
24. 24.⚡ What does this code show?
    let name = "Arjun";
    console.log("Hello, " + name + "!"); (a) Hello, Arjun! (b) Arjun (c) Hello, name! (d) name
25. 25.⚡ What does this code print? (Look at the quotes!)
    let x = "7";
    let y = 9;
    console.log(x + y); (a) 79 (b) 16 (c) Error
26. 26.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 7;
    console.log(x + y); (a) 16 (b) 97 (c) Error
27. 27.⚡ 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
28. 28.⚡ What number does this code print?
    let a = 53;
    let b = 14;
    console.log(a - b);
29. 29.⚡ What does this code show?
    let name = "Aman";
    console.log("Welcome, " + name + "!"); (a) Aman (b) name (c) Welcome, Aman! (d) Welcome, name!
30. 30.⚡ What number does this code print?
    let a = 49;
    let b = 12;
    console.log(a - b);
31. 31.⚡ 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
32. 32.⚡ Which tag holds JavaScript in a page? (a) <script> (b) <js> (c) <code> (d) <style>
33. 33.⚡ What does this code show?
    let name = "Zoya";
    console.log("Hi, " + name + "!"); (a) name (b) Hi, name! (c) Zoya (d) Hi, Zoya!
34. 34.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 7;
    console.log(x + y); (a) Error (b) 11 (c) 47
35. 35.⚡ What does this code show?
    let name = "Arjun";
    alert("Welcome, " + name + "!"); (a) Welcome, name! (b) Welcome, Arjun! (c) name (d) Arjun
36. 36.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 3;
    console.log(x + y); (a) Error (b) 13 (c) 4
37. 37.⚡ What does this code print? (Look at the quotes!)
    let x = "7";
    let y = 5;
    console.log(x + y); (a) Error (b) 12 (c) 75
38. 38.⚡ What number does this code print?
    let coins = 20;
    coins = coins + 9;
    coins = coins - 12;
    console.log(coins);
39. 39.⚡ What does this code show?
    let name = "Zoya";
    console.log("Hello, " + name + "!"); (a) name (b) Zoya (c) Hello, name! (d) Hello, Zoya!
40. 40.⚡ What number does this code print?
    let a = 46;
    let b = 11;
    console.log(a + b);

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