App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 981 · 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 backup (b) a cloud leaderboard (c) a shared chat (d) data saved on the phone
2. 2.True or false: notes to read offline fits saving on the phone. (a) True (b) False
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.💾 In most code, the first item of a list is at position ___. (a) 10 (b) 2 (c) 1 (d) 0
5. 5.💾 What number does this code show?
   let friends = ["Aman", "Zoya"];
   friends.push("Kabir");
   show(friends.length);
6. 6.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
7. 7.💾 pop() takes off the last item. What does this code show?
   let friends = ["Meera", "Riya", "Kabir"];
   friends.pop();
   show(friends[friends.length - 1]); (a) Kabir (b) Riya (c) Meera
8. 8.💾 What number does this code show?
   let score = 5;
   score = score - 2;
   score = score + 3;
   show(score);
9. 9.Which of these fits saving on the phone? (a) chat messages to friends (b) a class leaderboard (c) your last game level (d) photos on two devices
10. 10.True or false: a shared to-do list fits saving in the cloud. (a) False (b) True
11. 11.💾 Which can hold many values in order? (a) a list (b) a button (c) a switch (d) a single number
12. 12.💾 What number does this code show?
    let songs = ["Rain", "Ocean"];
    songs.push("Sunrise");
    songs.push("Stars");
    show(songs.length);
13. 13.💾 What number does this code show?
    let notes = ["Hindi", "Maths", "Science"];
    notes.push("Music");
    notes.push("Sports");
    show(notes.length);
14. 14.💾 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
15. 15.True or false: photos on two devices fits saving in the cloud. (a) False (b) True
16. 16.Which of these fits saving in the cloud? (a) the sound on/off setting (b) notes to read offline (c) your last game level (d) chat messages to friends
17. 17.💾 What does this code show? (Positions start at 0.)
    let friends = ["Meera", "Kabir", "Zoya"];
    show(friends[1]); (a) Kabir (b) Meera (c) Zoya
18. 18.💾 What does this code show? (Positions start at 0.)
    let friends = ["Zoya", "Arjun", "Kabir", "Riya", "Aman"];
    show(friends[2]); (a) Zoya (b) Arjun (c) Riya (d) Kabir
19. 19.💾 What is a variable? (a) a named box for a value (b) a phone setting (c) a picture (d) a type of screen
20. 20.💾 What number does this code show?
    let points = 3;
    points = points - 2;
    points = points + 4;
    show(points);
21. 21.💾 Where should the app save the sound on/off setting: on the phone or in the cloud? (a) in the cloud (b) on the phone
22. 22.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Sunrise", "Ocean"];
    show(songs[2]); (a) Ocean (b) Kites (c) Sunrise
23. 23.True or false: photos on two devices fits saving on the phone. (a) True (b) False
24. 24.True or false: your last game level fits saving in the cloud. (a) True (b) False
25. 25.Which of these fits saving in the cloud? (a) your last game level (b) a shared to-do list (c) a draft you are typing (d) the sound on/off setting
26. 26.💾 What number does this code show?
    let songs = ["Kites", "Sunrise", "Monsoon"];
    songs.push("Rain");
    show(songs.length);
27. 27.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
28. 28.💾 What number does this code show?
    let coins = 9;
    coins = coins - 3;
    coins = coins + 3;
    show(coins);
29. 29.💾 What does this code show? (Positions start at 0.)
    let songs = ["Ocean", "Sunrise", "Rain"];
    show(songs[2]); (a) Ocean (b) Rain (c) Sunrise
30. 30.💾 What number does this code show?
    let songs = ["Sunrise", "Ocean", "Stars"];
    songs.push("Monsoon");
    songs.push("Rain");
    show(songs.length);
31. 31.💾 What number does this code show?
    let notes = ["Art", "Science"];
    notes.push("Hindi");
    show(notes.length);
32. 32.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Ocean", "Kites", "Monsoon", "Stars"];
    show(songs[4]); (a) Ocean (b) Stars (c) Rain (d) Kites
33. 33.💾 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
34. 34.💾 pop() takes off the last item. What does this code show?
    let songs = ["Ocean", "Kites", "Monsoon"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Ocean (b) Kites (c) Monsoon
35. 35.💾 What number does this code show?
    let songs = ["Rain", "Kites", "Sunrise", "Stars"];
    songs.push("Monsoon");
    songs.push("Ocean");
    show(songs.length);
36. 36.💾 pop() takes off the last item. What does this code show?
    let songs = ["Monsoon", "Sunrise", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Kites (b) Monsoon (c) Sunrise
37. 37.💾 What number does this code show?
    let songs = ["Ocean", "Monsoon"];
    songs.push("Rain");
    show(songs.length);
38. 38.💾 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
39. 39.💾 pop() takes off the last item. What does this code show?
    let notes = ["Hindi", "Science", "Art", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Hindi (b) Science (c) Sports (d) Art
40. 40.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Aman", "Meera", "Zoya"];
    show(friends[0]); (a) Zoya (b) Riya (c) Meera (d) Aman

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