App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 578 · 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.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
2. 2.💾 What number does this code show?
   let lives = 7;
   lives = lives - 1;
   lives = lives + 2;
   show(lives);
3. 3.💾 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
4. 4.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
5. 5.💾 What number does this code show?
   let friends = ["Kabir", "Zoya"];
   friends.push("Meera");
   show(friends.length);
6. 6.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
7. 7.True or false: photos on two devices fits saving in the cloud. (a) False (b) True
8. 8.💾 Which works with no internet at all? (a) data saved on the phone (b) a cloud backup (c) a shared chat (d) a cloud leaderboard
9. 9.True or false: your last game level fits saving in the cloud. (a) True (b) False
10. 10.💾 Which can hold many values in order? (a) a switch (b) a single number (c) a button (d) a list
11. 11.💾 What number does this code show?
    let friends = ["Arjun", "Riya", "Aman", "Kabir"];
    friends.push("Meera");
    show(friends.length);
12. 12.💾 pop() takes off the last item. What does this code show?
    let notes = ["Hindi", "Sports", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Hindi (b) Music (c) Sports
13. 13.💾 pop() takes off the last item. What does this code show?
    let songs = ["Monsoon", "Sunrise", "Stars"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Sunrise (b) Stars (c) Monsoon
14. 14.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
15. 15.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
16. 16.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
17. 17.💾 What does this code show? (Positions start at 0.)
    let notes = ["Science", "Maths", "Art", "Hindi", "Music"];
    show(notes[1]); (a) Hindi (b) Science (c) Maths (d) Art
18. 18.Which of these fits saving in the cloud? (a) a class leaderboard (b) the sound on/off setting (c) your last game level (d) a draft you are typing
19. 19.💾 What number does this code show?
    let score = 5;
    score = score - 3;
    score = score + 3;
    show(score);
20. 20.Which of these fits saving on the phone? (a) chat messages to friends (b) a shared to-do list (c) your last game level (d) a class leaderboard
21. 21.💾 What number does this code show?
    let notes = ["Hindi", "Maths", "Art"];
    notes.push("Sports");
    notes.push("Music");
    show(notes.length);
22. 22.💾 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
23. 23.Which of these fits saving in the cloud? (a) the sound on/off setting (b) notes to read offline (c) photos on two devices (d) your last game level
24. 24.Which of these fits saving on the phone? (a) a shared to-do list (b) chat messages to friends (c) photos on two devices (d) notes to read offline
25. 25.💾 Data saved only on the phone is lost when ___. (a) the screen turns off (b) the app is closed (c) you send a message (d) the phone is lost
26. 26.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
27. 27.True or false: your last game level fits saving on the phone. (a) False (b) True
28. 28.💾 What is a variable? (a) a picture (b) a named box for a value (c) a phone setting (d) a type of screen
29. 29.💾 What number does this code show?
    let lives = 8;
    lives = lives - 1;
    lives = lives + 4;
    show(lives);
30. 30.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Art", "Hindi", "Science"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Science (c) Hindi (d) Maths
31. 31.💾 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
32. 32.💾 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) Music (c) Maths
33. 33.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
34. 34.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Kites", "Ocean", "Stars", "Monsoon"];
    show(songs[1]); (a) Ocean (b) Stars (c) Rain (d) Kites
35. 35.💾 Saving data in the cloud lets you ___. (a) use it on any device (b) shrink the app (c) never need a password (d) skip the internet
36. 36.💾 pop() takes off the last item. What does this code show?
    let friends = ["Riya", "Aman", "Kabir"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Aman (b) Kabir (c) Riya
37. 37.True or false: a draft you are typing fits saving on the phone. (a) True (b) False
38. 38.True or false: chat messages to friends fits saving in the cloud. (a) True (b) False
39. 39.💾 In most code, the first item of a list is at position ___. (a) 10 (b) 0 (c) 2 (d) 1
40. 40.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Sports", "Art"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Sports (b) Maths (c) Art

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