App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 122 · 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) in the cloud (b) on the phone
2. 2.Which of these fits saving in the cloud? (a) a draft you are typing (b) the sound on/off setting (c) notes to read offline (d) chat messages to friends
3. 3.💾 What number does this code show?
   let score = 4;
   score = score - 1;
   score = score + 3;
   show(score);
4. 4.True or false: a class leaderboard fits saving on the phone. (a) True (b) False
5. 5.💾 What number does this code show?
   let notes = ["Science", "Maths", "Art"];
   notes.push("Hindi");
   notes.push("Music");
   show(notes.length);
6. 6.True or false: notes to read offline fits saving on the phone. (a) True (b) False
7. 7.Which of these fits saving in the cloud? (a) the sound on/off setting (b) your last game level (c) a draft you are typing (d) a shared to-do list
8. 8.Which of these fits saving in the cloud? (a) a draft you are typing (b) your last game level (c) notes to read offline (d) a class leaderboard
9. 9.💾 pop() takes off the last item. What does this code show?
   let notes = ["Music", "Maths", "Hindi"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Hindi (b) Maths (c) Music
10. 10.💾 What does this code show? (Positions start at 0.)
    let notes = ["Hindi", "Maths", "Sports"];
    show(notes[0]); (a) Hindi (b) Maths (c) Sports
11. 11.Which of these fits saving in the cloud? (a) a draft you are typing (b) notes to read offline (c) the sound on/off setting (d) photos on two devices
12. 12.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
13. 13.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
14. 14.💾 What number does this code show?
    let points = 7;
    points = points - 2;
    points = points + 1;
    show(points);
15. 15.💾 What number does this code show?
    let stars = 9;
    stars = stars - 4;
    stars = stars + 1;
    show(stars);
16. 16.Which of these fits saving on the phone? (a) chat messages to friends (b) photos on two devices (c) a class leaderboard (d) a draft you are typing
17. 17.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Hindi", "Art", "Music"];
    show(notes[0]); (a) Art (b) Hindi (c) Maths (d) Music
18. 18.True or false: the sound on/off setting fits saving on the phone. (a) True (b) False
19. 19.💾 pop() takes off the last item. What does this code show?
    let songs = ["Ocean", "Rain", "Sunrise", "Monsoon", "Stars"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Rain (b) Ocean (c) Monsoon (d) Sunrise
20. 20.True or false: chat messages to friends fits saving on the phone. (a) False (b) True
21. 21.💾 What does this code show? (Positions start at 0.)
    let songs = ["Ocean", "Monsoon", "Rain"];
    show(songs[2]); (a) Monsoon (b) Rain (c) Ocean
22. 22.Which of these fits saving on the phone? (a) your last game level (b) chat messages to friends (c) photos on two devices (d) a shared to-do list
23. 23.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
24. 24.💾 What number does this code show?
    let coins = 9;
    coins = coins - 8;
    coins = coins + 1;
    show(coins);
25. 25.💾 Which can hold many values in order? (a) a switch (b) a button (c) a single number (d) a list
26. 26.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
27. 27.💾 What number does this code show?
    let coins = 5;
    coins = coins - 1;
    coins = coins + 4;
    show(coins);
28. 28.💾 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
29. 29.💾 What does this code show? (Positions start at 0.)
    let notes = ["Science", "Maths", "Art"];
    show(notes[2]); (a) Maths (b) Art (c) Science
30. 30.💾 What does this code show? (Positions start at 0.)
    let friends = ["Kabir", "Arjun", "Riya", "Aman", "Zoya"];
    show(friends[3]); (a) Arjun (b) Riya (c) Kabir (d) Aman
31. 31.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
32. 32.💾 In most code, the first item of a list is at position ___. (a) 10 (b) 1 (c) 2 (d) 0
33. 33.True or false: a shared to-do list fits saving in the cloud. (a) True (b) False
34. 34.💾 What number does this code show?
    let points = 6;
    points = points - 1;
    points = points + 1;
    show(points);
35. 35.💾 pop() takes off the last item. What does this code show?
    let songs = ["Kites", "Rain", "Sunrise", "Stars"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Stars (b) Rain (c) Kites (d) Sunrise
36. 36.💾 pop() takes off the last item. What does this code show?
    let friends = ["Meera", "Arjun", "Aman"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Arjun (b) Aman (c) Meera
37. 37.💾 What number does this code show?
    let friends = ["Arjun", "Meera"];
    friends.push("Riya");
    show(friends.length);
38. 38.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Science", "Music"];
    show(notes[2]); (a) Music (b) Sports (c) Science
39. 39.💾 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
40. 40.💾 What number does this code show?
    let friends = ["Kabir", "Aman", "Arjun", "Zoya"];
    friends.push("Riya");
    show(friends.length);

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