App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 410 · 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.💾 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
2. 2.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
3. 3.💾 What number does this code show?
   let notes = ["Maths", "Music", "Science"];
   notes.push("Sports");
   notes.push("Hindi");
   show(notes.length);
4. 4.Which of these fits saving in the cloud? (a) chat messages to friends (b) notes to read offline (c) the sound on/off setting (d) your last game level
5. 5.💾 What number does this code show?
   let friends = ["Aman", "Meera", "Zoya", "Arjun"];
   friends.push("Riya");
   show(friends.length);
6. 6.💾 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
7. 7.💾 Which works with no internet at all? (a) data saved on the phone (b) a shared chat (c) a cloud leaderboard (d) a cloud backup
8. 8.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
9. 9.💾 What does this code show? (Positions start at 0.)
   let friends = ["Arjun", "Aman", "Riya", "Zoya", "Kabir"];
   show(friends[4]); (a) Arjun (b) Kabir (c) Riya (d) Aman
10. 10.Which of these fits saving on the phone? (a) photos on two devices (b) chat messages to friends (c) a draft you are typing (d) a shared to-do list
11. 11.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
12. 12.Which of these fits saving in the cloud? (a) photos on two devices (b) a draft you are typing (c) your last game level (d) the sound on/off setting
13. 13.💾 What number does this code show?
    let friends = ["Meera", "Aman"];
    friends.push("Riya");
    friends.push("Zoya");
    show(friends.length);
14. 14.💾 In most code, the first item of a list is at position ___. (a) 2 (b) 10 (c) 0 (d) 1
15. 15.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Sports", "Music", "Art"];
    show(notes[0]); (a) Art (b) Music (c) Sports (d) Maths
16. 16.Which of these fits saving on the phone? (a) a shared to-do list (b) photos on two devices (c) chat messages to friends (d) the sound on/off setting
17. 17.True or false: chat messages to friends fits saving on the phone. (a) True (b) False
18. 18.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Art", "Hindi", "Science"];
    show(notes[2]); (a) Maths (b) Art (c) Science (d) Hindi
19. 19.True or false: your last game level fits saving on the phone. (a) False (b) True
20. 20.💾 Data saved only on the phone is lost when ___. (a) the screen turns off (b) the phone is lost (c) the app is closed (d) you send a message
21. 21.💾 Which can hold many values in order? (a) a switch (b) a list (c) a single number (d) a button
22. 22.💾 pop() takes off the last item. What does this code show?
    let songs = ["Stars", "Sunrise", "Rain"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Sunrise (b) Rain (c) Stars
23. 23.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Maths", "Hindi", "Music"];
    show(notes[0]); (a) Hindi (b) Art (c) Maths (d) Music
24. 24.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
25. 25.💾 What number does this code show?
    let songs = ["Ocean", "Sunrise", "Stars"];
    songs.push("Rain");
    songs.push("Kites");
    show(songs.length);
26. 26.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
27. 27.💾 pop() takes off the last item. What does this code show?
    let songs = ["Stars", "Rain", "Sunrise"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Sunrise (b) Stars (c) Rain
28. 28.Which of these fits saving on the phone? (a) photos on two devices (b) chat messages to friends (c) your last game level (d) a shared to-do list
29. 29.💾 What number does this code show?
    let songs = ["Monsoon", "Ocean", "Sunrise"];
    songs.push("Rain");
    songs.push("Stars");
    show(songs.length);
30. 30.True or false: photos on two devices fits saving on the phone. (a) True (b) False
31. 31.Which of these fits saving in the cloud? (a) a shared to-do list (b) your last game level (c) a draft you are typing (d) the sound on/off setting
32. 32.💾 What number does this code show?
    let songs = ["Stars", "Ocean"];
    songs.push("Rain");
    songs.push("Monsoon");
    show(songs.length);
33. 33.💾 pop() takes off the last item. What does this code show?
    let songs = ["Stars", "Ocean", "Sunrise", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Kites (b) Stars (c) Ocean (d) Sunrise
34. 34.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
35. 35.💾 Saving data in the cloud lets you ___. (a) shrink the app (b) skip the internet (c) use it on any device (d) never need a password
36. 36.True or false: the sound on/off setting fits saving in the cloud. (a) False (b) True
37. 37.💾 What number does this code show?
    let lives = 5;
    lives = lives - 3;
    lives = lives + 3;
    show(lives);
38. 38.💾 What number does this code show?
    let songs = ["Rain", "Stars"];
    songs.push("Kites");
    show(songs.length);
39. 39.💾 What number does this code show?
    let songs = ["Sunrise", "Kites"];
    songs.push("Ocean");
    songs.push("Rain");
    show(songs.length);
40. 40.💾 What number does this code show?
    let songs = ["Monsoon", "Rain"];
    songs.push("Ocean");
    songs.push("Stars");
    show(songs.length);

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