App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 662 · 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 does this code show? (Positions start at 0.)
   let notes = ["Maths", "Hindi", "Art"];
   show(notes[1]); (a) Hindi (b) Art (c) Maths
2. 2.💾 Which works with no internet at all? (a) a cloud leaderboard (b) data saved on the phone (c) a cloud backup (d) a shared chat
3. 3.Which of these fits saving on the phone? (a) chat messages to friends (b) a class leaderboard (c) photos on two devices (d) your last game level
4. 4.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
5. 5.Which of these fits saving in the cloud? (a) photos on two devices (b) a draft you are typing (c) the sound on/off setting (d) your last game level
6. 6.💾 What does this code show? (Positions start at 0.)
   let songs = ["Sunrise", "Rain", "Kites", "Ocean"];
   show(songs[1]); (a) Ocean (b) Kites (c) Rain (d) Sunrise
7. 7.True or false: a draft you are typing fits saving on the phone. (a) True (b) False
8. 8.💾 What number does this code show?
   let friends = ["Aman", "Zoya", "Kabir", "Meera"];
   friends.push("Riya");
   show(friends.length);
9. 9.Which of these fits saving on the phone? (a) a shared to-do list (b) a class leaderboard (c) chat messages to friends (d) notes to read offline
10. 10.💾 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
11. 11.💾 Data saved only on the phone is lost when ___. (a) the app is closed (b) the screen turns off (c) you send a message (d) the phone is lost
12. 12.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
13. 13.Which of these fits saving in the cloud? (a) a class leaderboard (b) notes to read offline (c) the sound on/off setting (d) a draft you are typing
14. 14.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True
15. 15.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
16. 16.💾 What does this code show? (Positions start at 0.)
    let friends = ["Zoya", "Kabir", "Arjun", "Aman"];
    show(friends[0]); (a) Zoya (b) Arjun (c) Aman (d) Kabir
17. 17.True or false: photos on two devices fits saving on the phone. (a) False (b) True
18. 18.Which of these fits saving on the phone? (a) chat messages to friends (b) the sound on/off setting (c) a class leaderboard (d) photos on two devices
19. 19.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
20. 20.💾 In most code, the first item of a list is at position ___. (a) 10 (b) 1 (c) 2 (d) 0
21. 21.True or false: a shared to-do list fits saving in the cloud. (a) False (b) True
22. 22.💾 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
23. 23.💾 pop() takes off the last item. What does this code show?
    let friends = ["Aman", "Kabir", "Zoya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Kabir (b) Aman (c) Zoya
24. 24.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
25. 25.💾 Which can hold many values in order? (a) a switch (b) a single number (c) a list (d) a button
26. 26.💾 pop() takes off the last item. What does this code show?
    let friends = ["Aman", "Riya", "Zoya", "Meera", "Arjun"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Aman (b) Zoya (c) Riya (d) Meera
27. 27.Which of these fits saving in the cloud? (a) a draft you are typing (b) notes to read offline (c) a shared to-do list (d) your last game level
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.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
30. 30.💾 What is a variable? (a) a picture (b) a phone setting (c) a named box for a value (d) a type of screen
31. 31.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
32. 32.💾 What number does this code show?
    let notes = ["Maths", "Hindi", "Science"];
    notes.push("Music");
    show(notes.length);
33. 33.💾 What number does this code show?
    let score = 5;
    score = score - 3;
    score = score + 1;
    show(score);
34. 34.💾 What number does this code show?
    let lives = 5;
    lives = lives - 5;
    lives = lives + 1;
    show(lives);
35. 35.💾 What number does this code show?
    let coins = 7;
    coins = coins - 3;
    coins = coins + 1;
    show(coins);
36. 36.💾 What number does this code show?
    let coins = 9;
    coins = coins - 6;
    coins = coins + 3;
    show(coins);
37. 37.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Art", "Science", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Sports (b) Science (c) Maths (d) Art
38. 38.💾 What number does this code show?
    let points = 7;
    points = points - 6;
    points = points + 4;
    show(points);
39. 39.💾 What number does this code show?
    let score = 4;
    score = score - 2;
    score = score + 2;
    show(score);
40. 40.💾 What number does this code show?
    let songs = ["Monsoon", "Kites", "Stars", "Ocean"];
    songs.push("Rain");
    show(songs.length);

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