App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 996 · 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 in the cloud. (a) True (b) False
2. 2.💾 pop() takes off the last item. What does this code show?
   let notes = ["Science", "Maths", "Art", "Hindi"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Hindi (b) Maths (c) Science (d) Art
3. 3.💾 pop() takes off the last item. What does this code show?
   let songs = ["Rain", "Sunrise", "Kites", "Monsoon"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Monsoon (b) Sunrise (c) Kites (d) Rain
4. 4.💾 What number does this code show?
   let score = 3;
   score = score - 2;
   score = score + 5;
   show(score);
5. 5.💾 What is a variable? (a) a type of screen (b) a picture (c) a phone setting (d) a named box for a value
6. 6.Which of these fits saving on the phone? (a) chat messages to friends (b) notes to read offline (c) photos on two devices (d) a class leaderboard
7. 7.True or false: chat messages to friends fits saving in the cloud. (a) True (b) False
8. 8.💾 What number does this code show?
   let songs = ["Monsoon", "Rain"];
   songs.push("Kites");
   songs.push("Ocean");
   show(songs.length);
9. 9.💾 What number does this code show?
   let stars = 9;
   stars = stars - 3;
   stars = stars + 2;
   show(stars);
10. 10.💾 Data saved only on the phone is lost when ___. (a) the app is closed (b) the screen turns off (c) you send a message (d) the phone is lost
11. 11.💾 What number does this code show?
    let songs = ["Monsoon", "Rain", "Sunrise"];
    songs.push("Kites");
    show(songs.length);
12. 12.💾 What does this code show? (Positions start at 0.)
    let friends = ["Arjun", "Zoya", "Kabir"];
    show(friends[0]); (a) Kabir (b) Arjun (c) Zoya
13. 13.💾 In most code, the first item of a list is at position ___. (a) 1 (b) 2 (c) 10 (d) 0
14. 14.💾 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
15. 15.💾 What number does this code show?
    let stars = 3;
    stars = stars - 2;
    stars = stars + 3;
    show(stars);
16. 16.💾 What number does this code show?
    let lives = 7;
    lives = lives - 6;
    lives = lives + 2;
    show(lives);
17. 17.True or false: photos on two devices fits saving in the cloud. (a) False (b) True
18. 18.💾 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
19. 19.💾 What number does this code show?
    let coins = 6;
    coins = coins - 4;
    coins = coins + 3;
    show(coins);
20. 20.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Hindi", "Maths"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Hindi (b) Maths (c) Art
21. 21.💾 What does this code show? (Positions start at 0.)
    let friends = ["Aman", "Zoya", "Riya", "Arjun"];
    show(friends[2]); (a) Zoya (b) Arjun (c) Riya (d) Aman
22. 22.💾 pop() takes off the last item. What does this code show?
    let friends = ["Zoya", "Kabir", "Arjun"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Kabir (b) Arjun (c) Zoya
23. 23.True or false: your last game level fits saving in the cloud. (a) True (b) False
24. 24.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
25. 25.💾 What number does this code show?
    let friends = ["Arjun", "Zoya"];
    friends.push("Meera");
    show(friends.length);
26. 26.Which of these fits saving in the cloud? (a) notes to read offline (b) a draft you are typing (c) your last game level (d) photos on two devices
27. 27.True or false: a class leaderboard fits saving on the phone. (a) True (b) False
28. 28.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Kabir", "Meera", "Aman"];
    show(friends[3]); (a) Riya (b) Aman (c) Meera (d) Kabir
29. 29.💾 Which can hold many values in order? (a) a single number (b) a list (c) a button (d) a switch
30. 30.Which of these fits saving in the cloud? (a) a draft you are typing (b) notes to read offline (c) a class leaderboard (d) the sound on/off setting
31. 31.Which of these fits saving in the cloud? (a) a draft you are typing (b) chat messages to friends (c) the sound on/off setting (d) notes to read offline
32. 32.💾 Where should the app save the sound on/off setting: on the phone or in the cloud? (a) on the phone (b) in the cloud
33. 33.Which of these fits saving on the phone? (a) your last game level (b) a shared to-do list (c) chat messages to friends (d) photos on two devices
34. 34.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Maths", "Music", "Art", "Hindi"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Music (c) Maths (d) Science
35. 35.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
36. 36.💾 What number does this code show?
    let stars = 8;
    stars = stars - 1;
    stars = stars + 5;
    show(stars);
37. 37.True or false: the sound on/off setting fits saving on the phone. (a) True (b) False
38. 38.💾 What number does this code show?
    let stars = 8;
    stars = stars - 2;
    stars = stars + 4;
    show(stars);
39. 39.💾 What does this code show? (Positions start at 0.)
    let friends = ["Aman", "Meera", "Arjun"];
    show(friends[2]); (a) Arjun (b) Aman (c) Meera
40. 40.💾 What number does this code show?
    let friends = ["Kabir", "Meera", "Arjun", "Aman"];
    friends.push("Zoya");
    show(friends.length);

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