JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 285 · 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 runs code when true? (a) for (b) let (c) if (d) console.log()
2. 2.⚡ What does alert() show? (a) a new tab (b) a table (c) a pop-up box (d) a picture
3. 3.⚡ What does this code print? (Look at the quotes!)
   let x = "8";
   let y = 1;
   console.log(x + y); (a) Error (b) 9 (c) 81
4. 4.⚡ Which JavaScript word writes in the console? (a) if (b) console.log() (c) alert() (d) for
5. 5.⚡ Which JavaScript word shows a pop-up box? (a) if (b) alert() (c) let (d) for
6. 6.⚡ Which JavaScript word repeats code? (a) for (b) let (c) if (d) console.log()
7. 7.⚡ Which word makes a new variable? (a) make (b) put (c) give (d) let
8. 8.⚡ What number does this code print?
   let marks = 26;
   marks = marks + 18;
   marks = marks - 12;
   console.log(marks);
9. 9.⚡ Where does console.log() show its output? (a) on the printer (b) on the title bar (c) in the console (d) in the address bar
10. 10.⚡ What number does this code print?
    let apples = 21;
    apples = apples + 9;
    apples = apples - 4;
    console.log(apples);
11. 11.⚡ Which tag holds JavaScript in a page? (a) <code> (b) <script> (c) <js> (d) <style>
12. 12.⚡ What does this code show?
    let name = "Zoya";
    alert("Well done, " + name + "!"); (a) Zoya (b) name (c) Well done, name! (d) Well done, Zoya!
13. 13.⚡ Which JavaScript word makes a new variable? (a) if (b) let (c) alert() (d) console.log()
14. 14.⚡ What does this code show?
    let name = "Aman";
    alert("Welcome, " + name + "!"); (a) name (b) Welcome, Aman! (c) Aman (d) Welcome, name!
15. 15.⚡ What number does this code print?
    let a = 36;
    let b = 15;
    console.log(a + b);
16. 16.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 6;
    console.log(x + y); (a) Error (b) 7 (c) 16
17. 17.⚡ What number does this code print?
    let apples = 12;
    apples = apples + 4;
    apples = apples - 6;
    console.log(apples);
18. 18.⚡ What number does this code print?
    let a = 32;
    let b = 11;
    console.log(a - b);
19. 19.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 7;
    console.log(x + y); (a) 10 (b) Error (c) 37
20. 20.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 8;
    console.log(x + y); (a) 48 (b) Error (c) 12
21. 21.⚡ What number does this code print?
    let a = 11;
    let b = 22;
    console.log(a + b);
22. 22.⚡ What does this code show?
    let name = "Aman";
    alert("Well done, " + name + "!"); (a) Well done, name! (b) Well done, Aman! (c) name (d) Aman
23. 23.⚡ 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
24. 24.⚡ What number does this code print?
    let a = 32;
    let b = 7;
    console.log(a - b);
25. 25.⚡ What number does this code print?
    let marks = 30;
    marks = marks + 19;
    marks = marks - 5;
    console.log(marks);
26. 26.⚡ What number does this code print?
    let books = 20;
    books = books + 7;
    books = books - 14;
    console.log(books);
27. 27.⚡ What number does this code print?
    let a = 21;
    let b = 12;
    console.log(a - b);
28. 28.⚡ What does this code show?
    let name = "Meera";
    alert("Hi, " + name + "!"); (a) Hi, name! (b) name (c) Meera (d) Hi, Meera!
29. 29.⚡ What does JavaScript add to a web page? (a) only colours (b) the domain name (c) the page title (d) actions and changes
30. 30.⚡ What number does this code print?
    let a = 29;
    let b = 7;
    console.log(a - b);
31. 31.⚡ What does this code show?
    let name = "Aman";
    alert("Hi, " + name + "!"); (a) Aman (b) Hi, Aman! (c) name (d) Hi, name!
32. 32.⚡ What number does this code print?
    let a = 10;
    let b = 8;
    console.log(a * b);
33. 33.⚡ What number does this code print?
    let books = 13;
    books = books + 8;
    books = books - 9;
    console.log(books);
34. 34.⚡ What number does this code print?
    let a = 48;
    let b = 15;
    console.log(a + b);
35. 35.⚡ What does this code show?
    let name = "Kabir";
    alert("Well done, " + name + "!"); (a) Kabir (b) Well done, name! (c) Well done, Kabir! (d) name
36. 36.⚡ What does this code show?
    let name = "Arjun";
    alert("Hi, " + name + "!"); (a) Hi, name! (b) name (c) Hi, Arjun! (d) Arjun
37. 37.⚡ What does this code show?
    let name = "Zoya";
    console.log("Welcome, " + name + "!"); (a) Welcome, Zoya! (b) Zoya (c) name (d) Welcome, name!
38. 38.⚡ What number does this code print?
    let marks = 17;
    marks = marks + 6;
    marks = marks - 22;
    console.log(marks);
39. 39.⚡ What number does this code print?
    let a = 51;
    let b = 26;
    console.log(a - b);
40. 40.⚡ What does this code show?
    let name = "Riya";
    console.log("Well done, " + name + "!"); (a) name (b) Well done, name! (c) Well done, Riya! (d) Riya

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