App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 935 · 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.💾 Saving data in the cloud lets you ___. (a) never need a password (b) shrink the app (c) skip the internet (d) use it on any device
2. 2.True or false: photos on two devices fits saving in the cloud. (a) False (b) True
3. 3.💾 What number does this code show?
   let friends = ["Arjun", "Meera"];
   friends.push("Kabir");
   show(friends.length);
4. 4.Which of these fits saving in the cloud? (a) chat messages to friends (b) the sound on/off setting (c) your last game level (d) a draft you are typing
5. 5.Which of these fits saving on the phone? (a) a class leaderboard (b) chat messages to friends (c) a shared to-do list (d) your last game level
6. 6.💾 What number does this code show?
   let notes = ["Maths", "Hindi", "Sports", "Science"];
   notes.push("Art");
   notes.push("Music");
   show(notes.length);
7. 7.True or false: notes to read offline fits saving on the phone. (a) True (b) False
8. 8.💾 Which can hold many values in order? (a) a single number (b) a button (c) a switch (d) a list
9. 9.💾 What number does this code show?
   let friends = ["Arjun", "Zoya", "Meera"];
   friends.push("Kabir");
   friends.push("Riya");
   show(friends.length);
10. 10.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True
11. 11.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
12. 12.💾 What number does this code show?
    let songs = ["Monsoon", "Stars", "Sunrise"];
    songs.push("Rain");
    show(songs.length);
13. 13.💾 What number does this code show?
    let score = 9;
    score = score - 4;
    score = score + 5;
    show(score);
14. 14.💾 What number does this code show?
    let points = 4;
    points = points - 4;
    points = points + 1;
    show(points);
15. 15.💾 Where should the app save photos on two devices: 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) photos on two devices (b) chat messages to friends (c) a shared to-do list (d) the sound on/off setting
17. 17.💾 What number does this code show?
    let points = 6;
    points = points - 6;
    points = points + 3;
    show(points);
18. 18.💾 pop() takes off the last item. What does this code show?
    let friends = ["Riya", "Arjun", "Zoya", "Kabir", "Aman"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Arjun (b) Zoya (c) Kabir (d) Riya
19. 19.💾 Data saved only on the phone is lost when ___. (a) you send a message (b) the screen turns off (c) the phone is lost (d) the app is closed
20. 20.💾 What number does this code show?
    let coins = 4;
    coins = coins - 2;
    coins = coins + 1;
    show(coins);
21. 21.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
22. 22.💾 What number does this code show?
    let friends = ["Arjun", "Kabir"];
    friends.push("Zoya");
    friends.push("Aman");
    show(friends.length);
23. 23.💾 What number does this code show?
    let friends = ["Riya", "Arjun"];
    friends.push("Zoya");
    show(friends.length);
24. 24.True or false: photos on two devices fits saving on the phone. (a) True (b) False
25. 25.💾 What number does this code show?
    let stars = 9;
    stars = stars - 4;
    stars = stars + 1;
    show(stars);
26. 26.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Arjun", "Zoya", "Kabir", "Meera"];
    show(friends[3]); (a) Zoya (b) Arjun (c) Kabir (d) Riya
27. 27.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Music", "Science"];
    show(notes[2]); (a) Music (b) Science (c) Sports
28. 28.💾 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
29. 29.💾 Which works with no internet at all? (a) a cloud backup (b) a shared chat (c) a cloud leaderboard (d) data saved on the phone
30. 30.💾 What number does this code show?
    let friends = ["Riya", "Meera", "Arjun"];
    friends.push("Kabir");
    friends.push("Zoya");
    show(friends.length);
31. 31.Which of these fits saving on the phone? (a) photos on two devices (b) a shared to-do list (c) chat messages to friends (d) a draft you are typing
32. 32.💾 What number does this code show?
    let stars = 4;
    stars = stars - 2;
    stars = stars + 4;
    show(stars);
33. 33.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Science", "Maths", "Hindi", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Maths (b) Art (c) Science (d) Hindi
34. 34.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
35. 35.💾 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
36. 36.💾 What is a variable? (a) a phone setting (b) a named box for a value (c) a picture (d) a type of screen
37. 37.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
38. 38.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
39. 39.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
40. 40.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Sports", "Art", "Science", "Hindi"];
    show(notes[3]); (a) Sports (b) Art (c) Science (d) Music

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