App Dev Worksheet: Variables, Lists and Saving

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

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