JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 506 · 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) for (b) alert() (c) let (d) console.log()
2. 2.⚡ What does this code show?
   let name = "Zoya";
   alert("Welcome, " + name + "!"); (a) name (b) Zoya (c) Welcome, Zoya! (d) Welcome, name!
3. 3.⚡ What does this code print? (Look at the quotes!)
   let x = "9";
   let y = 4;
   console.log(x + y); (a) Error (b) 13 (c) 94
4. 4.⚡ What number does this code print?
   let a = 30;
   let b = 20;
   console.log(a + b);
5. 5.⚡ What number does this code print?
   let a = 44;
   let b = 38;
   console.log(a + b);
6. 6.⚡ Which JavaScript word writes in the console? (a) if (b) for (c) alert() (d) console.log()
7. 7.⚡ A JavaScript file usually ends with which extension? (a) .css (b) .html (c) .js (d) .jpg
8. 8.⚡ Which JavaScript word makes a new variable? (a) console.log() (b) for (c) if (d) let
9. 9.⚡ Where does console.log() show its output? (a) in the address bar (b) in the console (c) on the printer (d) on the title bar
10. 10.⚡ What number does this code print?
    let a = 11;
    let b = 12;
    console.log(a * b);
11. 11.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 4;
    console.log(x + y); (a) 6 (b) 24 (c) Error
12. 12.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 2;
    console.log(x + y); (a) 52 (b) 7 (c) Error
13. 13.⚡ Which JavaScript word repeats code? (a) if (b) alert() (c) console.log() (d) for
14. 14.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 1;
    console.log(x + y); (a) Error (b) 2 (c) 11
15. 15.⚡ What number does this code print?
    let a = 28;
    let b = 11;
    console.log(a - b);
16. 16.⚡ What does this code show?
    let name = "Arjun";
    console.log("Hi, " + name + "!"); (a) Hi, name! (b) name (c) Hi, Arjun! (d) Arjun
17. 17.⚡ What number does this code print?
    let apples = 11;
    apples = apples + 3;
    apples = apples - 7;
    console.log(apples);
18. 18.⚡ What does alert() show? (a) a new tab (b) a pop-up box (c) a picture (d) a table
19. 19.⚡ What does JavaScript add to a web page? (a) only colours (b) the domain name (c) the page title (d) actions and changes
20. 20.⚡ What does this code show?
    let name = "Riya";
    alert("Hi, " + name + "!"); (a) Riya (b) Hi, name! (c) name (d) Hi, Riya!
21. 21.⚡ Which word makes a new variable? (a) give (b) make (c) put (d) let
22. 22.⚡ What number does this code print?
    let a = 7;
    let b = 10;
    console.log(a * b);
23. 23.⚡ What number does this code print?
    let a = 46;
    let b = 21;
    console.log(a - b);
24. 24.⚡ What number does this code print?
    let a = 9;
    let b = 8;
    console.log(a - b);
25. 25.⚡ What number does this code print?
    let a = 11;
    let b = 10;
    console.log(a * b);
26. 26.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 4;
    console.log(x + y); (a) Error (b) 64 (c) 10
27. 27.⚡ What number does this code print?
    let a = 40;
    let b = 8;
    console.log(a + b);
28. 28.⚡ What does this code show?
    let name = "Meera";
    console.log("Hi, " + name + "!"); (a) Hi, name! (b) Hi, Meera! (c) name (d) Meera
29. 29.⚡ What does this code show?
    let name = "Aman";
    alert("Hi, " + name + "!"); (a) Hi, name! (b) Aman (c) name (d) Hi, Aman!
30. 30.⚡ What number does this code print?
    let apples = 11;
    apples = apples + 5;
    apples = apples - 13;
    console.log(apples);
31. 31.⚡ What number does this code print?
    let a = 55;
    let b = 2;
    console.log(a + b);
32. 32.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 8;
    console.log(x + y); (a) Error (b) 18 (c) 9
33. 33.⚡ What number does this code print?
    let a = 32;
    let b = 17;
    console.log(a + b);
34. 34.⚡ What number does this code print?
    let marks = 24;
    marks = marks + 4;
    marks = marks - 12;
    console.log(marks);
35. 35.⚡ What number does this code print?
    let a = 4;
    let b = 11;
    console.log(a * b);
36. 36.⚡ What number does this code print?
    let score = 17;
    score = score + 10;
    score = score - 23;
    console.log(score);
37. 37.⚡ What number does this code print?
    let a = 56;
    let b = 9;
    console.log(a + b);
38. 38.⚡ What number does this code print?
    let a = 4;
    let b = 12;
    console.log(a * b);
39. 39.⚡ What does this code show?
    let name = "Riya";
    console.log("Well done, " + name + "!"); (a) Well done, name! (b) Well done, Riya! (c) Riya (d) name
40. 40.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 7;
    console.log(x + y); (a) Error (b) 87 (c) 15

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