JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 155 · 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) alert() (b) if (c) for (d) console.log()
2. 2.⚡ Which JavaScript word repeats code? (a) for (b) console.log() (c) let (d) alert()
3. 3.⚡ What does this code show?
   let name = "Aman";
   console.log("Welcome, " + name + "!"); (a) Aman (b) Welcome, name! (c) name (d) Welcome, Aman!
4. 4.⚡ What does this code print? (Look at the quotes!)
   let x = "9";
   let y = 3;
   console.log(x + y); (a) 93 (b) 12 (c) Error
5. 5.⚡ What number does this code print?
   let a = 46;
   let b = 37;
   console.log(a + b);
6. 6.⚡ What number does this code print?
   let marks = 11;
   marks = marks + 11;
   marks = marks - 8;
   console.log(marks);
7. 7.⚡ What does this code print? (Look at the quotes!)
   let x = "1";
   let y = 9;
   console.log(x + y); (a) 19 (b) 10 (c) Error
8. 8.⚡ What number does this code print?
   let a = 5;
   let b = 2;
   console.log(a * b);
9. 9.⚡ What does this code show?
   let name = "Riya";
   alert("Hi, " + name + "!"); (a) Riya (b) Hi, Riya! (c) Hi, name! (d) name
10. 10.⚡ What number does this code print?
    let books = 21;
    books = books + 9;
    books = books - 5;
    console.log(books);
11. 11.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 6;
    console.log(x + y); (a) 14 (b) 86 (c) Error
12. 12.⚡ What number does this code print?
    let score = 10;
    score = score + 17;
    score = score - 19;
    console.log(score);
13. 13.⚡ What number does this code print?
    let runs = 19;
    runs = runs + 5;
    runs = runs - 5;
    console.log(runs);
14. 14.⚡ What number does this code print?
    let runs = 6;
    runs = runs + 16;
    runs = runs - 7;
    console.log(runs);
15. 15.⚡ Which tag holds JavaScript in a page? (a) <style> (b) <js> (c) <script> (d) <code>
16. 16.⚡ What does this code show?
    let name = "Aman";
    alert("Welcome, " + name + "!"); (a) name (b) Welcome, Aman! (c) Welcome, name! (d) Aman
17. 17.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 8;
    console.log(x + y); (a) 88 (b) Error (c) 16
18. 18.⚡ What does alert() show? (a) a pop-up box (b) a table (c) a picture (d) a new tab
19. 19.⚡ Which JavaScript word shows a pop-up box? (a) if (b) alert() (c) for (d) let
20. 20.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 6;
    console.log(x + y); (a) 46 (b) 10 (c) Error
21. 21.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 1;
    console.log(x + y); (a) 61 (b) Error (c) 7
22. 22.⚡ What does this code print? (Look at the quotes!)
    let x = "7";
    let y = 6;
    console.log(x + y); (a) 76 (b) 13 (c) Error
23. 23.⚡ What does this code show?
    let name = "Aman";
    alert("Hello, " + name + "!"); (a) Aman (b) Hello, Aman! (c) Hello, name! (d) name
24. 24.⚡ What number does this code print?
    let apples = 12;
    apples = apples + 16;
    apples = apples - 9;
    console.log(apples);
25. 25.⚡ What number does this code print?
    let a = 55;
    let b = 1;
    console.log(a + b);
26. 26.⚡ What does this code show?
    let name = "Aman";
    console.log("Well done, " + name + "!"); (a) Well done, Aman! (b) Aman (c) name (d) Well done, name!
27. 27.⚡ What does this code show?
    let name = "Zoya";
    console.log("Hello, " + name + "!"); (a) Hello, name! (b) Hello, Zoya! (c) name (d) Zoya
28. 28.⚡ What does this code show?
    let name = "Arjun";
    console.log("Hi, " + name + "!"); (a) Hi, Arjun! (b) name (c) Hi, name! (d) Arjun
29. 29.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 8;
    console.log(x + y); (a) 10 (b) Error (c) 28
30. 30.⚡ What does this code show?
    let name = "Zoya";
    console.log("Welcome, " + name + "!"); (a) Welcome, name! (b) name (c) Welcome, Zoya! (d) Zoya
31. 31.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 6;
    console.log(x + y); (a) Error (b) 15 (c) 96
32. 32.⚡ A JavaScript file usually ends with which extension? (a) .css (b) .html (c) .js (d) .jpg
33. 33.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 5;
    console.log(x + y); (a) Error (b) 7 (c) 25
34. 34.⚡ What does this code show?
    let name = "Riya";
    console.log("Welcome, " + name + "!"); (a) Welcome, Riya! (b) name (c) Riya (d) Welcome, name!
35. 35.⚡ Which word makes a new variable? (a) put (b) let (c) make (d) give
36. 36.⚡ What number does this code print?
    let a = 23;
    let b = 8;
    console.log(a - b);
37. 37.⚡ Which JavaScript word writes in the console? (a) alert() (b) let (c) console.log() (d) for
38. 38.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 1;
    console.log(x + y); (a) Error (b) 11 (c) 2
39. 39.⚡ Which JavaScript word makes a new variable? (a) alert() (b) let (c) if (d) console.log()
40. 40.⚡ What number does this code print?
    let books = 22;
    books = books + 7;
    books = books - 8;
    console.log(books);

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