App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 257 · 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 the sound on/off setting: on the phone or in the cloud? (a) on the phone (b) in the cloud
2. 2.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
3. 3.Which of these fits saving in the cloud? (a) a shared to-do list (b) a draft you are typing (c) your last game level (d) the sound on/off setting
4. 4.💾 Saving data in the cloud lets you ___. (a) never need a password (b) use it on any device (c) skip the internet (d) shrink the app
5. 5.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
6. 6.💾 What does this code show? (Positions start at 0.)
   let songs = ["Kites", "Rain", "Monsoon", "Stars", "Sunrise"];
   show(songs[0]); (a) Kites (b) Monsoon (c) Rain (d) Stars
7. 7.True or false: the sound on/off setting fits saving in the cloud. (a) False (b) True
8. 8.True or false: a draft you are typing fits saving on the phone. (a) True (b) False
9. 9.💾 What number does this code show?
   let notes = ["Music", "Hindi"];
   notes.push("Science");
   show(notes.length);
10. 10.💾 Which works with no internet at all? (a) a cloud backup (b) a shared chat (c) data saved on the phone (d) a cloud leaderboard
11. 11.💾 pop() takes off the last item. What does this code show?
    let friends = ["Arjun", "Kabir", "Aman", "Riya", "Zoya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Aman (b) Kabir (c) Arjun (d) Riya
12. 12.💾 What is a variable? (a) a picture (b) a named box for a value (c) a phone setting (d) a type of screen
13. 13.💾 pop() takes off the last item. What does this code show?
    let friends = ["Aman", "Riya", "Zoya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Riya (b) Zoya (c) Aman
14. 14.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
15. 15.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Sunrise", "Kites"];
    show(songs[0]); (a) Rain (b) Sunrise (c) Kites
16. 16.💾 What does this code show? (Positions start at 0.)
    let friends = ["Arjun", "Kabir", "Aman", "Meera"];
    show(friends[2]); (a) Meera (b) Arjun (c) Kabir (d) Aman
17. 17.True or false: a shared to-do list fits saving in the cloud. (a) False (b) True
18. 18.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
19. 19.💾 In most code, the first item of a list is at position ___. (a) 2 (b) 0 (c) 1 (d) 10
20. 20.💾 What number does this code show?
    let notes = ["Art", "Hindi"];
    notes.push("Sports");
    notes.push("Maths");
    show(notes.length);
21. 21.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Music", "Science"];
    show(notes[0]); (a) Science (b) Sports (c) Music
22. 22.💾 What does this code show? (Positions start at 0.)
    let songs = ["Ocean", "Stars", "Sunrise"];
    show(songs[2]); (a) Stars (b) Sunrise (c) Ocean
23. 23.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
24. 24.💾 pop() takes off the last item. What does this code show?
    let notes = ["Hindi", "Maths", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Sports (b) Maths (c) Hindi
25. 25.💾 Where should the app save a shared to-do list: on the phone or in the cloud? (a) on the phone (b) in the cloud
26. 26.True or false: chat messages to friends fits saving on the phone. (a) True (b) False
27. 27.Which of these fits saving in the cloud? (a) chat messages to friends (b) a draft you are typing (c) your last game level (d) notes to read offline
28. 28.True or false: your last game level fits saving in the cloud. (a) False (b) True
29. 29.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
30. 30.Which of these fits saving on the phone? (a) chat messages to friends (b) a shared to-do list (c) photos on two devices (d) a draft you are typing
31. 31.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
32. 32.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Hindi", "Music"];
    show(notes[0]); (a) Music (b) Art (c) Hindi
33. 33.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
34. 34.💾 What number does this code show?
    let score = 9;
    score = score - 3;
    score = score + 1;
    show(score);
35. 35.💾 What does this code show? (Positions start at 0.)
    let notes = ["Hindi", "Maths", "Science", "Sports"];
    show(notes[0]); (a) Maths (b) Hindi (c) Science (d) Sports
36. 36.💾 What does this code show? (Positions start at 0.)
    let friends = ["Kabir", "Riya", "Zoya", "Aman"];
    show(friends[2]); (a) Aman (b) Zoya (c) Kabir (d) Riya
37. 37.💾 pop() takes off the last item. What does this code show?
    let friends = ["Kabir", "Meera", "Zoya", "Riya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Meera (b) Kabir (c) Riya (d) Zoya
38. 38.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
39. 39.💾 What number does this code show?
    let friends = ["Kabir", "Arjun", "Aman", "Meera"];
    friends.push("Riya");
    show(friends.length);
40. 40.Which of these fits saving on the phone? (a) a class leaderboard (b) your last game level (c) a shared to-do list (d) photos on two devices

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