App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 471 · 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: notes to read offline fits saving on the phone. (a) True (b) False
2. 2.Which of these fits saving on the phone? (a) chat messages to friends (b) photos on two devices (c) a class leaderboard (d) notes to read offline
3. 3.💾 What does this code show? (Positions start at 0.)
   let notes = ["Science", "Art", "Music", "Sports"];
   show(notes[0]); (a) Music (b) Sports (c) Science (d) Art
4. 4.True or false: your last game level fits saving in the cloud. (a) True (b) False
5. 5.💾 In most code, the first item of a list is at position ___. (a) 10 (b) 2 (c) 1 (d) 0
6. 6.Which of these fits saving on the phone? (a) a shared to-do list (b) photos on two devices (c) a class leaderboard (d) a draft you are typing
7. 7.Which of these fits saving in the cloud? (a) notes to read offline (b) chat messages to friends (c) the sound on/off setting (d) a draft you are typing
8. 8.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
9. 9.💾 What number does this code show?
   let score = 8;
   score = score - 8;
   score = score + 3;
   show(score);
10. 10.💾 What is a variable? (a) a named box for a value (b) a phone setting (c) a type of screen (d) a picture
11. 11.💾 What number does this code show?
    let friends = ["Riya", "Arjun"];
    friends.push("Aman");
    show(friends.length);
12. 12.💾 What does this code show? (Positions start at 0.)
    let friends = ["Kabir", "Meera", "Aman", "Zoya"];
    show(friends[1]); (a) Aman (b) Meera (c) Kabir (d) Zoya
13. 13.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
14. 14.💾 Which works with no internet at all? (a) a shared chat (b) data saved on the phone (c) a cloud backup (d) a cloud leaderboard
15. 15.💾 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
16. 16.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
17. 17.💾 What number does this code show?
    let friends = ["Meera", "Aman", "Kabir", "Riya"];
    friends.push("Zoya");
    show(friends.length);
18. 18.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
19. 19.💾 What number does this code show?
    let songs = ["Stars", "Rain", "Sunrise"];
    songs.push("Monsoon");
    songs.push("Kites");
    show(songs.length);
20. 20.💾 pop() takes off the last item. What does this code show?
    let friends = ["Meera", "Zoya", "Aman", "Kabir", "Riya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Kabir (b) Aman (c) Zoya (d) Meera
21. 21.💾 What number does this code show?
    let lives = 4;
    lives = lives - 2;
    lives = lives + 2;
    show(lives);
22. 22.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) photos on two devices
23. 23.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
24. 24.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Kites", "Ocean", "Rain", "Sunrise"];
    show(songs[2]); (a) Ocean (b) Rain (c) Monsoon (d) Kites
25. 25.True or false: chat messages to friends fits saving in the cloud. (a) True (b) False
26. 26.💾 pop() takes off the last item. What does this code show?
    let notes = ["Music", "Science", "Maths", "Sports", "Hindi"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Music (b) Maths (c) Sports (d) Science
27. 27.True or false: your last game level fits saving on the phone. (a) True (b) False
28. 28.💾 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
29. 29.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
30. 30.💾 What number does this code show?
    let friends = ["Arjun", "Kabir", "Meera", "Zoya"];
    friends.push("Aman");
    show(friends.length);
31. 31.💾 Which can hold many values in order? (a) a single number (b) a list (c) a button (d) a switch
32. 32.💾 pop() takes off the last item. What does this code show?
    let friends = ["Zoya", "Aman", "Meera"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Meera (b) Zoya (c) Aman
33. 33.True or false: a shared to-do list fits saving on the phone. (a) True (b) False
34. 34.True or false: photos on two devices fits saving on the phone. (a) True (b) False
35. 35.💾 What does this code show? (Positions start at 0.)
    let friends = ["Arjun", "Meera", "Kabir", "Aman"];
    show(friends[0]); (a) Meera (b) Arjun (c) Aman (d) Kabir
36. 36.💾 What number does this code show?
    let notes = ["Sports", "Science", "Hindi", "Maths"];
    notes.push("Art");
    show(notes.length);
37. 37.💾 pop() takes off the last item. What does this code show?
    let songs = ["Stars", "Kites", "Ocean", "Rain"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Stars (b) Ocean (c) Kites (d) Rain
38. 38.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Maths", "Art", "Hindi", "Science"];
    show(notes[3]); (a) Music (b) Maths (c) Art (d) Hindi
39. 39.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Monsoon", "Kites", "Sunrise"];
    show(songs[0]); (a) Kites (b) Rain (c) Monsoon (d) Sunrise
40. 40.💾 pop() takes off the last item. What does this code show?
    let songs = ["Stars", "Sunrise", "Monsoon"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Sunrise (b) Monsoon (c) Stars

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