App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 117 · 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: notes to read offline fits saving in the cloud. (a) False (b) True
2. 2.💾 pop() takes off the last item. What does this code show?
   let songs = ["Kites", "Sunrise", "Ocean", "Monsoon"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Kites (b) Monsoon (c) Ocean (d) Sunrise
3. 3.💾 What does this code show? (Positions start at 0.)
   let notes = ["Art", "Science", "Sports", "Hindi", "Maths"];
   show(notes[0]); (a) Science (b) Art (c) Hindi (d) Sports
4. 4.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
5. 5.💾 pop() takes off the last item. What does this code show?
   let songs = ["Rain", "Kites", "Sunrise"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Kites (b) Rain (c) Sunrise
6. 6.Which of these fits saving in the cloud? (a) notes to read offline (b) a shared to-do list (c) the sound on/off setting (d) a draft you are typing
7. 7.💾 pop() takes off the last item. What does this code show?
   let songs = ["Rain", "Ocean", "Sunrise", "Monsoon", "Kites"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Sunrise (b) Monsoon (c) Rain (d) Ocean
8. 8.💾 Where should the app save a shared to-do list: on the phone or in the cloud? (a) in the cloud (b) on the phone
9. 9.💾 Which works with no internet at all? (a) data saved on the phone (b) a cloud backup (c) a cloud leaderboard (d) a shared chat
10. 10.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
11. 11.💾 Which can hold many values in order? (a) a button (b) a switch (c) a list (d) a single number
12. 12.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Science", "Art", "Music", "Hindi"];
    show(notes[3]); (a) Art (b) Maths (c) Music (d) Science
13. 13.True or false: notes to read offline fits saving on the phone. (a) True (b) False
14. 14.💾 In most code, the first item of a list is at position ___. (a) 10 (b) 0 (c) 2 (d) 1
15. 15.💾 pop() takes off the last item. What does this code show?
    let friends = ["Kabir", "Zoya", "Meera", "Aman", "Arjun"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Aman (b) Zoya (c) Kabir (d) Meera
16. 16.Which of these fits saving in the cloud? (a) your last game level (b) notes to read offline (c) a class leaderboard (d) the sound on/off setting
17. 17.True or false: a class leaderboard fits saving on the phone. (a) True (b) False
18. 18.💾 pop() takes off the last item. What does this code show?
    let friends = ["Zoya", "Kabir", "Riya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Kabir (b) Zoya (c) Riya
19. 19.💾 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
20. 20.💾 What number does this code show?
    let notes = ["Art", "Science", "Hindi", "Maths"];
    notes.push("Music");
    show(notes.length);
21. 21.💾 What number does this code show?
    let songs = ["Kites", "Ocean", "Rain", "Monsoon"];
    songs.push("Sunrise");
    show(songs.length);
22. 22.True or false: a class leaderboard fits saving in the cloud. (a) True (b) False
23. 23.Which of these fits saving on the phone? (a) photos on two devices (b) chat messages to friends (c) the sound on/off setting (d) a shared to-do list
24. 24.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Sports", "Maths"];
    show(notes[0]); (a) Music (b) Maths (c) Sports
25. 25.💾 What number does this code show?
    let notes = ["Art", "Music"];
    notes.push("Sports");
    notes.push("Hindi");
    show(notes.length);
26. 26.💾 What number does this code show?
    let score = 9;
    score = score - 1;
    score = score + 4;
    show(score);
27. 27.💾 pop() takes off the last item. What does this code show?
    let friends = ["Aman", "Zoya", "Riya", "Arjun"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Zoya (b) Riya (c) Aman (d) Arjun
28. 28.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
29. 29.💾 Saving data in the cloud lets you ___. (a) skip the internet (b) never need a password (c) shrink the app (d) use it on any device
30. 30.💾 What does this code show? (Positions start at 0.)
    let songs = ["Stars", "Monsoon", "Kites"];
    show(songs[2]); (a) Kites (b) Stars (c) Monsoon
31. 31.Which of these fits saving on the phone? (a) chat messages to friends (b) photos on two devices (c) notes to read offline (d) a class leaderboard
32. 32.💾 What does this code show? (Positions start at 0.)
    let songs = ["Ocean", "Sunrise", "Kites", "Stars"];
    show(songs[0]); (a) Sunrise (b) Stars (c) Kites (d) Ocean
33. 33.💾 What number does this code show?
    let notes = ["Sports", "Maths"];
    notes.push("Science");
    notes.push("Art");
    show(notes.length);
34. 34.True or false: a shared to-do list fits saving in the cloud. (a) True (b) False
35. 35.💾 What does this code show? (Positions start at 0.)
    let friends = ["Aman", "Riya", "Zoya"];
    show(friends[0]); (a) Riya (b) Zoya (c) Aman
36. 36.Which of these fits saving on the phone? (a) photos on two devices (b) a class leaderboard (c) a shared to-do list (d) your last game level
37. 37.True or false: chat messages to friends fits saving on the phone. (a) False (b) True
38. 38.True or false: your last game level fits saving on the phone. (a) True (b) False
39. 39.True or false: photos on two devices fits saving on the phone. (a) True (b) False
40. 40.💾 What number does this code show?
    let notes = ["Maths", "Science"];
    notes.push("Sports");
    notes.push("Hindi");
    show(notes.length);

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