App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 541 · 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.💾 Which works with no internet at all? (a) a cloud leaderboard (b) data saved on the phone (c) a cloud backup (d) a shared chat
2. 2.💾 What does this code show? (Positions start at 0.)
   let songs = ["Sunrise", "Stars", "Rain", "Kites", "Ocean"];
   show(songs[0]); (a) Rain (b) Sunrise (c) Kites (d) Stars
3. 3.💾 What number does this code show?
   let coins = 3;
   coins = coins - 1;
   coins = coins + 4;
   show(coins);
4. 4.💾 Which can hold many values in order? (a) a switch (b) a button (c) a list (d) a single number
5. 5.💾 What number does this code show?
   let songs = ["Stars", "Monsoon"];
   songs.push("Kites");
   show(songs.length);
6. 6.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
7. 7.💾 What does this code show? (Positions start at 0.)
   let notes = ["Sports", "Art", "Maths", "Science", "Music"];
   show(notes[4]); (a) Sports (b) Music (c) Art (d) Maths
8. 8.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
9. 9.💾 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
10. 10.True or false: photos on two devices fits saving on the phone. (a) True (b) False
11. 11.💾 What number does this code show?
    let points = 3;
    points = points - 2;
    points = points + 2;
    show(points);
12. 12.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
13. 13.Which of these fits saving on the phone? (a) a class leaderboard (b) chat messages to friends (c) photos on two devices (d) your last game level
14. 14.💾 Data saved only on the phone is lost when ___. (a) the app is closed (b) the screen turns off (c) the phone is lost (d) you send a message
15. 15.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Stars", "Rain", "Ocean"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Stars (b) Ocean (c) Sunrise (d) Rain
16. 16.Which of these fits saving on the phone? (a) chat messages to friends (b) a shared to-do list (c) a draft you are typing (d) a class leaderboard
17. 17.Which of these fits saving in the cloud? (a) notes to read offline (b) a draft you are typing (c) the sound on/off setting (d) photos on two devices
18. 18.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
19. 19.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Art", "Sports"];
    show(notes[0]); (a) Sports (b) Art (c) Maths
20. 20.Which of these fits saving in the cloud? (a) chat messages to friends (b) the sound on/off setting (c) your last game level (d) notes to read offline
21. 21.💾 What is a variable? (a) a type of screen (b) a named box for a value (c) a phone setting (d) a picture
22. 22.💾 What does this code show? (Positions start at 0.)
    let notes = ["Hindi", "Maths", "Science", "Music", "Art"];
    show(notes[0]); (a) Music (b) Maths (c) Hindi (d) Science
23. 23.Which of these fits saving on the phone? (a) photos on two devices (b) the sound on/off setting (c) chat messages to friends (d) a shared to-do list
24. 24.Which of these fits saving in the cloud? (a) the sound on/off setting (b) a draft you are typing (c) a shared to-do list (d) notes to read offline
25. 25.Which of these fits saving on the phone? (a) photos on two devices (b) chat messages to friends (c) a class leaderboard (d) notes to read offline
26. 26.💾 In most code, the first item of a list is at position ___. (a) 1 (b) 2 (c) 10 (d) 0
27. 27.💾 What number does this code show?
    let score = 4;
    score = score - 1;
    score = score + 5;
    show(score);
28. 28.💾 What number does this code show?
    let songs = ["Rain", "Ocean", "Sunrise"];
    songs.push("Monsoon");
    show(songs.length);
29. 29.True or false: chat messages to friends fits saving on the phone. (a) True (b) False
30. 30.💾 What number does this code show?
    let notes = ["Art", "Sports"];
    notes.push("Maths");
    show(notes.length);
31. 31.💾 What number does this code show?
    let score = 6;
    score = score - 4;
    score = score + 3;
    show(score);
32. 32.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
33. 33.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
34. 34.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Rain", "Monsoon", "Stars", "Sunrise"];
    show(songs[4]); (a) Monsoon (b) Rain (c) Sunrise (d) Kites
35. 35.💾 Saving data in the cloud lets you ___. (a) skip the internet (b) shrink the app (c) use it on any device (d) never need a password
36. 36.💾 What number does this code show?
    let notes = ["Science", "Art"];
    notes.push("Hindi");
    show(notes.length);
37. 37.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Sports", "Hindi", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Maths (b) Sports (c) Music (d) Hindi
38. 38.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Hindi", "Sports", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Music (c) Sports (d) Hindi
39. 39.Which of these fits saving in the cloud? (a) your last game level (b) a class leaderboard (c) a draft you are typing (d) notes to read offline
40. 40.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Music", "Maths"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Maths (c) Music

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