App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 73 · 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.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
2. 2.💾 In most code, the first item of a list is at position ___. (a) 10 (b) 2 (c) 0 (d) 1
3. 3.💾 What does this code show? (Positions start at 0.)
   let notes = ["Sports", "Art", "Hindi"];
   show(notes[0]); (a) Sports (b) Art (c) Hindi
4. 4.True or false: a shared to-do list fits saving in the cloud. (a) False (b) True
5. 5.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
6. 6.Which of these fits saving in the cloud? (a) your last game level (b) a draft you are typing (c) the sound on/off setting (d) photos on two devices
7. 7.💾 Where should the app save a draft you are typing: on the phone or in the cloud? (a) in the cloud (b) on the phone
8. 8.💾 What does this code show? (Positions start at 0.)
   let songs = ["Stars", "Ocean", "Sunrise", "Rain"];
   show(songs[2]); (a) Rain (b) Ocean (c) Sunrise (d) Stars
9. 9.💾 What is a variable? (a) a picture (b) a named box for a value (c) a type of screen (d) a phone setting
10. 10.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Sports", "Music", "Science"];
    show(notes[2]); (a) Maths (b) Sports (c) Science (d) Music
11. 11.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Music", "Maths", "Hindi"];
    show(notes[1]); (a) Hindi (b) Music (c) Maths (d) Art
12. 12.💾 What does this code show? (Positions start at 0.)
    let friends = ["Meera", "Zoya", "Kabir", "Aman"];
    show(friends[2]); (a) Zoya (b) Aman (c) Meera (d) Kabir
13. 13.True or false: chat messages to friends fits saving on the phone. (a) False (b) True
14. 14.💾 What does this code show? (Positions start at 0.)
    let friends = ["Arjun", "Aman", "Zoya", "Kabir", "Meera"];
    show(friends[3]); (a) Aman (b) Kabir (c) Arjun (d) Zoya
15. 15.💾 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
16. 16.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Maths", "Hindi"];
    show(notes[0]); (a) Hindi (b) Maths (c) Music
17. 17.💾 What number does this code show?
    let coins = 8;
    coins = coins - 6;
    coins = coins + 3;
    show(coins);
18. 18.💾 Saving data in the cloud lets you ___. (a) skip the internet (b) shrink the app (c) use it on any device (d) never need a password
19. 19.True or false: your last game level fits saving in the cloud. (a) True (b) False
20. 20.💾 What number does this code show?
    let coins = 4;
    coins = coins - 1;
    coins = coins + 4;
    show(coins);
21. 21.💾 What number does this code show?
    let points = 7;
    points = points - 1;
    points = points + 4;
    show(points);
22. 22.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
23. 23.True or false: a class leaderboard fits saving on the phone. (a) True (b) False
24. 24.True or false: notes to read offline fits saving on the phone. (a) False (b) True
25. 25.Which of these fits saving on the phone? (a) a class leaderboard (b) a shared to-do list (c) a draft you are typing (d) chat messages to friends
26. 26.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
27. 27.💾 What number does this code show?
    let coins = 7;
    coins = coins - 5;
    coins = coins + 2;
    show(coins);
28. 28.💾 What number does this code show?
    let notes = ["Maths", "Hindi", "Art", "Science"];
    notes.push("Sports");
    notes.push("Music");
    show(notes.length);
29. 29.💾 Which can hold many values in order? (a) a switch (b) a list (c) a button (d) a single number
30. 30.💾 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
31. 31.Which of these fits saving on the phone? (a) photos on two devices (b) a shared to-do list (c) your last game level (d) chat messages to friends
32. 32.💾 What number does this code show?
    let coins = 4;
    coins = coins - 4;
    coins = coins + 2;
    show(coins);
33. 33.💾 What number does this code show?
    let points = 3;
    points = points - 1;
    points = points + 1;
    show(points);
34. 34.💾 pop() takes off the last item. What does this code show?
    let notes = ["Sports", "Maths", "Science"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Sports (b) Science (c) Maths
35. 35.💾 What does this code show? (Positions start at 0.)
    let friends = ["Arjun", "Kabir", "Meera", "Riya"];
    show(friends[2]); (a) Kabir (b) Arjun (c) Riya (d) Meera
36. 36.💾 What number does this code show?
    let friends = ["Arjun", "Kabir"];
    friends.push("Aman");
    friends.push("Riya");
    show(friends.length);
37. 37.💾 Which works with no internet at all? (a) a cloud leaderboard (b) a cloud backup (c) data saved on the phone (d) a shared chat
38. 38.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Science", "Art"];
    show(notes[2]); (a) Sports (b) Science (c) Art
39. 39.💾 What number does this code show?
    let score = 3;
    score = score - 1;
    score = score + 4;
    show(score);
40. 40.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Sunrise", "Kites", "Stars", "Monsoon"];
    show(songs[2]); (a) Rain (b) Sunrise (c) Stars (d) Kites

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