App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 962 · 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 friends = ["Zoya", "Riya", "Kabir", "Aman"];
   show(friends[3]); (a) Aman (b) Kabir (c) Riya (d) Zoya
2. 2.Which of these fits saving on the phone? (a) a draft you are typing (b) chat messages to friends (c) a class leaderboard (d) photos on two devices
3. 3.💾 pop() takes off the last item. What does this code show?
   let songs = ["Rain", "Ocean", "Monsoon", "Stars"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Stars (b) Monsoon (c) Rain (d) Ocean
4. 4.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
5. 5.💾 What number does this code show?
   let lives = 9;
   lives = lives - 4;
   lives = lives + 4;
   show(lives);
6. 6.True or false: notes to read offline fits saving on the phone. (a) False (b) True
7. 7.💾 What does this code show? (Positions start at 0.)
   let friends = ["Riya", "Aman", "Zoya", "Kabir"];
   show(friends[3]); (a) Zoya (b) Kabir (c) Riya (d) Aman
8. 8.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
9. 9.💾 Saving data in the cloud lets you ___. (a) never need a password (b) skip the internet (c) use it on any device (d) shrink the app
10. 10.💾 What is a variable? (a) a phone setting (b) a named box for a value (c) a type of screen (d) a picture
11. 11.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
12. 12.True or false: photos on two devices fits saving in the cloud. (a) True (b) False
13. 13.True or false: a shared to-do list fits saving on the phone. (a) True (b) False
14. 14.True or false: a class leaderboard fits saving on the phone. (a) True (b) False
15. 15.💾 What number does this code show?
    let friends = ["Riya", "Kabir", "Aman"];
    friends.push("Meera");
    friends.push("Arjun");
    show(friends.length);
16. 16.💾 pop() takes off the last item. What does this code show?
    let friends = ["Arjun", "Meera", "Zoya", "Riya", "Kabir"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Riya (b) Arjun (c) Meera (d) Zoya
17. 17.💾 What number does this code show?
    let friends = ["Arjun", "Meera", "Zoya"];
    friends.push("Aman");
    show(friends.length);
18. 18.Which of these fits saving on the phone? (a) a shared to-do list (b) a class leaderboard (c) the sound on/off setting (d) photos on two devices
19. 19.💾 What does this code show? (Positions start at 0.)
    let notes = ["Science", "Art", "Hindi"];
    show(notes[0]); (a) Hindi (b) Science (c) Art
20. 20.💾 What number does this code show?
    let score = 3;
    score = score - 2;
    score = score + 4;
    show(score);
21. 21.Which of these fits saving on the phone? (a) chat messages to friends (b) a class leaderboard (c) a shared to-do list (d) notes to read offline
22. 22.💾 Which can hold many values in order? (a) a switch (b) a single number (c) a list (d) a button
23. 23.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
24. 24.💾 Which works with no internet at all? (a) a cloud leaderboard (b) a shared chat (c) a cloud backup (d) data saved on the phone
25. 25.Which of these fits saving on the phone? (a) a shared to-do list (b) your last game level (c) a class leaderboard (d) photos on two devices
26. 26.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
27. 27.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Maths", "Hindi", "Sports", "Science"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Hindi (b) Sports (c) Maths (d) Art
28. 28.💾 What number does this code show?
    let score = 5;
    score = score - 1;
    score = score + 1;
    show(score);
29. 29.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Rain", "Ocean"];
    show(songs[2]); (a) Ocean (b) Rain (c) Kites
30. 30.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Science", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Art (c) Music
31. 31.💾 What number does this code show?
    let friends = ["Zoya", "Kabir", "Meera"];
    friends.push("Riya");
    friends.push("Arjun");
    show(friends.length);
32. 32.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Monsoon", "Ocean", "Rain"];
    show(songs[0]); (a) Monsoon (b) Rain (c) Kites (d) Ocean
33. 33.💾 What number does this code show?
    let coins = 5;
    coins = coins - 5;
    coins = coins + 1;
    show(coins);
34. 34.Which of these fits saving in the cloud? (a) notes to read offline (b) photos on two devices (c) a draft you are typing (d) the sound on/off setting
35. 35.💾 What number does this code show?
    let notes = ["Music", "Maths", "Science", "Hindi"];
    notes.push("Art");
    show(notes.length);
36. 36.💾 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
37. 37.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
38. 38.💾 What does this code show? (Positions start at 0.)
    let notes = ["Hindi", "Music", "Science"];
    show(notes[2]); (a) Hindi (b) Music (c) Science
39. 39.💾 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
40. 40.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Kites", "Ocean", "Monsoon"];
    show(songs[2]); (a) Kites (b) Sunrise (c) Ocean (d) Monsoon

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