App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 265 · 40 questions

Developer's tip (Box, list, place): A variable holds one value; a list holds many in order. Positions start at 0. push adds to the end; pop takes off the last item; length is how many items. On the phone: works offline, private. In the cloud: shared, any device, needs the internet.

1. 1.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
2. 2.💾 What number does this code show?
   let songs = ["Sunrise", "Monsoon", "Ocean", "Stars"];
   songs.push("Rain");
   show(songs.length);
3. 3.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
4. 4.💾 Data saved only on the phone is lost when ___. (a) you send a message (b) the app is closed (c) the screen turns off (d) the phone is lost
5. 5.💾 What does this code show? (Positions start at 0.)
   let notes = ["Science", "Music", "Maths"];
   show(notes[1]); (a) Science (b) Music (c) Maths
6. 6.💾 What number does this code show?
   let coins = 6;
   coins = coins - 3;
   coins = coins + 1;
   show(coins);
7. 7.Which of these fits saving on the phone? (a) a class leaderboard (b) the sound on/off setting (c) chat messages to friends (d) a shared to-do list
8. 8.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
9. 9.💾 What number does this code show?
   let songs = ["Monsoon", "Kites", "Stars"];
   songs.push("Rain");
   show(songs.length);
10. 10.💾 What is a variable? (a) a type of screen (b) a named box for a value (c) a picture (d) a phone setting
11. 11.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
12. 12.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Hindi", "Maths", "Music", "Sports"];
    show(notes[1]); (a) Art (b) Hindi (c) Music (d) Maths
13. 13.💾 What number does this code show?
    let notes = ["Art", "Maths", "Sports", "Hindi"];
    notes.push("Science");
    show(notes.length);
14. 14.True or false: photos on two devices fits saving in the cloud. (a) False (b) True
15. 15.Which of these fits saving on the phone? (a) notes to read offline (b) chat messages to friends (c) a class leaderboard (d) photos on two devices
16. 16.💾 Which works with no internet at all? (a) a cloud backup (b) data saved on the phone (c) a cloud leaderboard (d) a shared chat
17. 17.True or false: a class leaderboard fits saving on the phone. (a) True (b) False
18. 18.True or false: a shared to-do list fits saving in the cloud. (a) True (b) False
19. 19.True or false: the sound on/off setting fits saving on the phone. (a) True (b) False
20. 20.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True
21. 21.💾 What number does this code show?
    let coins = 3;
    coins = coins - 1;
    coins = coins + 2;
    show(coins);
22. 22.💾 Saving data in the cloud lets you ___. (a) use it on any device (b) skip the internet (c) shrink the app (d) never need a password
23. 23.💾 What does this code show? (Positions start at 0.)
    let notes = ["Hindi", "Music", "Art"];
    show(notes[2]); (a) Art (b) Music (c) Hindi
24. 24.💾 What number does this code show?
    let songs = ["Kites", "Rain", "Ocean", "Sunrise"];
    songs.push("Stars");
    songs.push("Monsoon");
    show(songs.length);
25. 25.💾 What number does this code show?
    let points = 3;
    points = points - 1;
    points = points + 4;
    show(points);
26. 26.💾 What number does this code show?
    let songs = ["Sunrise", "Rain", "Stars", "Ocean"];
    songs.push("Kites");
    show(songs.length);
27. 27.True or false: your last game level fits saving on the phone. (a) False (b) True
28. 28.💾 What number does this code show?
    let score = 8;
    score = score - 2;
    score = score + 5;
    show(score);
29. 29.💾 Where should the app save a draft you are typing: on the phone or in the cloud? (a) on the phone (b) in the cloud
30. 30.💾 pop() takes off the last item. What does this code show?
    let notes = ["Hindi", "Maths", "Art", "Science", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Hindi (b) Art (c) Science (d) Maths
31. 31.💾 pop() takes off the last item. What does this code show?
    let notes = ["Hindi", "Maths", "Science"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Hindi (c) Maths
32. 32.💾 Which can hold many values in order? (a) a single number (b) a button (c) a list (d) a switch
33. 33.💾 What does this code show? (Positions start at 0.)
    let songs = ["Ocean", "Monsoon", "Sunrise"];
    show(songs[0]); (a) Sunrise (b) Monsoon (c) Ocean
34. 34.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Science", "Maths"];
    show(notes[2]); (a) Sports (b) Maths (c) Science
35. 35.💾 What number does this code show?
    let songs = ["Stars", "Sunrise", "Monsoon", "Kites"];
    songs.push("Rain");
    songs.push("Ocean");
    show(songs.length);
36. 36.💾 Where should the app save the sound on/off setting: on the phone or in the cloud? (a) on the phone (b) in the cloud
37. 37.💾 In most code, the first item of a list is at position ___. (a) 0 (b) 2 (c) 10 (d) 1
38. 38.True or false: a shared to-do list fits saving on the phone. (a) False (b) True
39. 39.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Hindi", "Science", "Art"];
    show(notes[2]); (a) Science (b) Sports (c) Hindi (d) Art
40. 40.💾 What number does this code show?
    let score = 6;
    score = score - 6;
    score = score + 5;
    show(score);

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