App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 811 · 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.💾 What number does this code show?
   let friends = ["Riya", "Arjun", "Kabir", "Meera"];
   friends.push("Zoya");
   show(friends.length);
2. 2.💾 What does this code show? (Positions start at 0.)
   let songs = ["Stars", "Monsoon", "Sunrise"];
   show(songs[0]); (a) Sunrise (b) Stars (c) Monsoon
3. 3.💾 What number does this code show?
   let friends = ["Meera", "Aman", "Arjun", "Riya"];
   friends.push("Zoya");
   show(friends.length);
4. 4.True or false: a shared to-do list fits saving in the cloud. (a) False (b) True
5. 5.Which of these fits saving on the phone? (a) photos on two devices (b) a class leaderboard (c) notes to read offline (d) a shared to-do list
6. 6.True or false: your last game level fits saving in the cloud. (a) True (b) False
7. 7.💾 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
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.💾 What does this code show? (Positions start at 0.)
   let songs = ["Stars", "Ocean", "Monsoon", "Rain", "Kites"];
   show(songs[1]); (a) Rain (b) Monsoon (c) Ocean (d) Stars
10. 10.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
11. 11.Which of these fits saving in the cloud? (a) notes to read offline (b) the sound on/off setting (c) a draft you are typing (d) photos on two devices
12. 12.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
13. 13.💾 In most code, the first item of a list is at position ___. (a) 2 (b) 0 (c) 10 (d) 1
14. 14.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
15. 15.💾 What number does this code show?
    let songs = ["Rain", "Sunrise", "Monsoon", "Stars"];
    songs.push("Ocean");
    songs.push("Kites");
    show(songs.length);
16. 16.💾 Where should the app save a draft you are typing: on the phone or in the cloud? (a) in the cloud (b) on the phone
17. 17.💾 What number does this code show?
    let notes = ["Music", "Hindi", "Sports", "Art"];
    notes.push("Maths");
    show(notes.length);
18. 18.💾 What number does this code show?
    let points = 4;
    points = points - 3;
    points = points + 1;
    show(points);
19. 19.Which of these fits saving on the phone? (a) chat messages to friends (b) a shared to-do list (c) the sound on/off setting (d) a class leaderboard
20. 20.💾 What does this code show? (Positions start at 0.)
    let friends = ["Meera", "Riya", "Arjun", "Zoya", "Aman"];
    show(friends[3]); (a) Riya (b) Arjun (c) Meera (d) Zoya
21. 21.💾 What number does this code show?
    let lives = 7;
    lives = lives - 3;
    lives = lives + 3;
    show(lives);
22. 22.💾 pop() takes off the last item. What does this code show?
    let notes = ["Hindi", "Art", "Science", "Maths", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Hindi (b) Art (c) Maths (d) Science
23. 23.💾 What number does this code show?
    let score = 9;
    score = score - 1;
    score = score + 2;
    show(score);
24. 24.💾 pop() takes off the last item. What does this code show?
    let notes = ["Sports", "Science", "Maths", "Art"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Sports (b) Science (c) Art (d) Maths
25. 25.💾 pop() takes off the last item. What does this code show?
    let notes = ["Sports", "Science", "Maths", "Hindi"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Sports (c) Maths (d) Hindi
26. 26.💾 What number does this code show?
    let songs = ["Kites", "Sunrise"];
    songs.push("Rain");
    show(songs.length);
27. 27.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
28. 28.💾 pop() takes off the last item. What does this code show?
    let notes = ["Music", "Maths", "Art", "Science"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Maths (c) Music (d) Science
29. 29.Which of these fits saving on the phone? (a) a class leaderboard (b) a shared to-do list (c) photos on two devices (d) a draft you are typing
30. 30.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True
31. 31.Which of these fits saving in the cloud? (a) notes to read offline (b) your last game level (c) chat messages to friends (d) a draft you are typing
32. 32.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
33. 33.💾 What number does this code show?
    let songs = ["Kites", "Monsoon"];
    songs.push("Stars");
    songs.push("Rain");
    show(songs.length);
34. 34.💾 Which can hold many values in order? (a) a switch (b) a single number (c) a button (d) a list
35. 35.💾 What number does this code show?
    let lives = 8;
    lives = lives - 1;
    lives = lives + 5;
    show(lives);
36. 36.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
37. 37.💾 What number does this code show?
    let points = 5;
    points = points - 4;
    points = points + 2;
    show(points);
38. 38.Which of these fits saving in the cloud? (a) a draft you are typing (b) your last game level (c) a shared to-do list (d) notes to read offline
39. 39.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
40. 40.💾 Which works with no internet at all? (a) a shared chat (b) a cloud leaderboard (c) data saved on the phone (d) a cloud backup

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