App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 7 · 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: photos on two devices fits saving on the phone. (a) True (b) False
2. 2.💾 What number does this code show?
   let friends = ["Riya", "Kabir", "Arjun", "Meera"];
   friends.push("Aman");
   friends.push("Zoya");
   show(friends.length);
3. 3.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
4. 4.💾 What does this code show? (Positions start at 0.)
   let friends = ["Riya", "Kabir", "Aman"];
   show(friends[0]); (a) Aman (b) Riya (c) Kabir
5. 5.💾 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
6. 6.💾 pop() takes off the last item. What does this code show?
   let songs = ["Ocean", "Kites", "Rain", "Stars", "Monsoon"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Rain (b) Stars (c) Kites (d) Ocean
7. 7.Which of these fits saving on the phone? (a) photos on two devices (b) a shared to-do list (c) a draft you are typing (d) chat messages to friends
8. 8.💾 pop() takes off the last item. What does this code show?
   let songs = ["Stars", "Rain", "Ocean", "Kites", "Monsoon"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Kites (b) Stars (c) Ocean (d) Rain
9. 9.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
10. 10.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
11. 11.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) a class leaderboard
12. 12.💾 What number does this code show?
    let friends = ["Riya", "Aman", "Meera", "Zoya"];
    friends.push("Arjun");
    show(friends.length);
13. 13.Which of these fits saving on the phone? (a) a class leaderboard (b) a shared to-do list (c) chat messages to friends (d) notes to read offline
14. 14.💾 pop() takes off the last item. What does this code show?
    let friends = ["Kabir", "Riya", "Aman", "Arjun"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Riya (b) Kabir (c) Arjun (d) Aman
15. 15.Which of these fits saving on the phone? (a) a class leaderboard (b) photos on two devices (c) your last game level (d) a shared to-do list
16. 16.💾 pop() takes off the last item. What does this code show?
    let songs = ["Kites", "Sunrise", "Rain", "Monsoon"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Rain (b) Sunrise (c) Monsoon (d) Kites
17. 17.💾 pop() takes off the last item. What does this code show?
    let friends = ["Kabir", "Aman", "Riya", "Arjun"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Kabir (b) Arjun (c) Riya (d) Aman
18. 18.💾 What number does this code show?
    let stars = 7;
    stars = stars - 7;
    stars = stars + 3;
    show(stars);
19. 19.💾 In most code, the first item of a list is at position ___. (a) 0 (b) 2 (c) 10 (d) 1
20. 20.True or false: a shared to-do list fits saving in the cloud. (a) True (b) False
21. 21.💾 Saving data in the cloud lets you ___. (a) shrink the app (b) skip the internet (c) never need a password (d) use it on any device
22. 22.True or false: chat messages to friends fits saving on the phone. (a) True (b) False
23. 23.True or false: your last game level fits saving on the phone. (a) False (b) True
24. 24.💾 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
25. 25.💾 What number does this code show?
    let score = 3;
    score = score - 2;
    score = score + 4;
    show(score);
26. 26.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
27. 27.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Hindi", "Maths", "Science"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Hindi (c) Maths (d) Science
28. 28.💾 What number does this code show?
    let friends = ["Arjun", "Riya"];
    friends.push("Aman");
    show(friends.length);
29. 29.💾 Where should the app save a shared to-do list: on the phone or in the cloud? (a) in the cloud (b) on the phone
30. 30.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
31. 31.💾 What number does this code show?
    let notes = ["Maths", "Hindi", "Science"];
    notes.push("Art");
    show(notes.length);
32. 32.Which of these fits saving in the cloud? (a) photos on two devices (b) notes to read offline (c) your last game level (d) the sound on/off setting
33. 33.💾 What number does this code show?
    let songs = ["Rain", "Sunrise", "Stars", "Monsoon"];
    songs.push("Kites");
    songs.push("Ocean");
    show(songs.length);
34. 34.💾 Which can hold many values in order? (a) a switch (b) a single number (c) a list (d) a button
35. 35.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
36. 36.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
37. 37.💾 What number does this code show?
    let coins = 9;
    coins = coins - 9;
    coins = coins + 3;
    show(coins);
38. 38.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Art", "Science"];
    show(notes[2]); (a) Art (b) Science (c) Sports
39. 39.💾 What number does this code show?
    let songs = ["Rain", "Sunrise", "Kites"];
    songs.push("Stars");
    songs.push("Ocean");
    show(songs.length);
40. 40.True or false: your last game level fits saving in the cloud. (a) False (b) True

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