App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 946 · 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 songs = ["Rain", "Kites", "Ocean"];
   show(songs[0]); (a) Ocean (b) Kites (c) Rain
2. 2.💾 Which can hold many values in order? (a) a single number (b) a list (c) a switch (d) a button
3. 3.💾 Saving data in the cloud lets you ___. (a) use it on any device (b) skip the internet (c) never need a password (d) shrink the app
4. 4.True or false: your last game level fits saving in the cloud. (a) True (b) False
5. 5.💾 pop() takes off the last item. What does this code show?
   let notes = ["Art", "Maths", "Sports", "Science"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Science (b) Sports (c) Art (d) Maths
6. 6.💾 What does this code show? (Positions start at 0.)
   let notes = ["Music", "Art", "Maths"];
   show(notes[0]); (a) Maths (b) Music (c) Art
7. 7.💾 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
8. 8.True or false: photos on two devices fits saving in the cloud. (a) False (b) True
9. 9.💾 What does this code show? (Positions start at 0.)
   let songs = ["Ocean", "Kites", "Stars", "Sunrise", "Rain"];
   show(songs[2]); (a) Sunrise (b) Ocean (c) Stars (d) Kites
10. 10.💾 Which works with no internet at all? (a) a shared chat (b) a cloud leaderboard (c) a cloud backup (d) data saved on the phone
11. 11.💾 pop() takes off the last item. What does this code show?
    let songs = ["Kites", "Ocean", "Sunrise"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Sunrise (b) Ocean (c) Kites
12. 12.💾 What number does this code show?
    let notes = ["Music", "Science"];
    notes.push("Art");
    show(notes.length);
13. 13.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) chat messages to friends
14. 14.True or false: chat messages to friends fits saving in the cloud. (a) True (b) False
15. 15.True or false: photos on two devices fits saving on the phone. (a) False (b) True
16. 16.💾 What is a variable? (a) a phone setting (b) a picture (c) a type of screen (d) a named box for a value
17. 17.💾 What number does this code show?
    let notes = ["Science", "Music"];
    notes.push("Art");
    notes.push("Maths");
    show(notes.length);
18. 18.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
19. 19.True or false: chat messages to friends fits saving on the phone. (a) True (b) False
20. 20.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
21. 21.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
22. 22.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Hindi", "Sports", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Hindi (b) Sports (c) Maths (d) Music
23. 23.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Science", "Music", "Sports", "Art"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Maths (b) Science (c) Sports (d) Music
24. 24.💾 In most code, the first item of a list is at position ___. (a) 0 (b) 2 (c) 1 (d) 10
25. 25.True or false: a shared to-do list fits saving on the phone. (a) True (b) False
26. 26.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
27. 27.Which of these fits saving on the phone? (a) a shared to-do list (b) a class leaderboard (c) photos on two devices (d) notes to read offline
28. 28.True or false: a draft you are typing fits saving on the phone. (a) True (b) False
29. 29.💾 What number does this code show?
    let coins = 3;
    coins = coins - 1;
    coins = coins + 3;
    show(coins);
30. 30.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Science", "Sports", "Maths", "Music"];
    show(notes[1]); (a) Maths (b) Sports (c) Science (d) Art
31. 31.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
32. 32.💾 What number does this code show?
    let friends = ["Kabir", "Zoya"];
    friends.push("Riya");
    friends.push("Meera");
    show(friends.length);
33. 33.True or false: the sound on/off setting fits saving in the cloud. (a) False (b) True
34. 34.Which of these fits saving in the cloud? (a) a shared to-do list (b) your last game level (c) the sound on/off setting (d) a draft you are typing
35. 35.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
36. 36.💾 What does this code show? (Positions start at 0.)
    let notes = ["Science", "Sports", "Maths"];
    show(notes[0]); (a) Maths (b) Sports (c) Science
37. 37.💾 What number does this code show?
    let friends = ["Riya", "Aman"];
    friends.push("Zoya");
    friends.push("Arjun");
    show(friends.length);
38. 38.💾 What number does this code show?
    let notes = ["Hindi", "Music", "Science"];
    notes.push("Sports");
    show(notes.length);
39. 39.💾 What number does this code show?
    let friends = ["Kabir", "Riya", "Meera"];
    friends.push("Arjun");
    show(friends.length);
40. 40.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone

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