App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 290 · 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.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
3. 3.💾 What does this code show? (Positions start at 0.)
   let notes = ["Art", "Science", "Maths", "Hindi", "Music"];
   show(notes[0]); (a) Science (b) Art (c) Maths (d) Hindi
4. 4.💾 pop() takes off the last item. What does this code show?
   let songs = ["Sunrise", "Ocean", "Rain", "Stars"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Sunrise (b) Ocean (c) Stars (d) Rain
5. 5.Which of these fits saving on the phone? (a) a draft you are typing (b) photos on two devices (c) a shared to-do list (d) chat messages to friends
6. 6.💾 What number does this code show?
   let songs = ["Sunrise", "Ocean"];
   songs.push("Stars");
   show(songs.length);
7. 7.Which of these fits saving on the phone? (a) chat messages to friends (b) a class leaderboard (c) photos on two devices (d) notes to read offline
8. 8.💾 What number does this code show?
   let songs = ["Kites", "Stars", "Sunrise", "Rain"];
   songs.push("Ocean");
   songs.push("Monsoon");
   show(songs.length);
9. 9.💾 What number does this code show?
   let notes = ["Science", "Art", "Maths", "Music"];
   notes.push("Hindi");
   show(notes.length);
10. 10.Which of these fits saving on the phone? (a) a class leaderboard (b) photos on two devices (c) a shared to-do list (d) your last game level
11. 11.💾 What is a variable? (a) a picture (b) a named box for a value (c) a type of screen (d) a phone setting
12. 12.💾 What does this code show? (Positions start at 0.)
    let friends = ["Aman", "Kabir", "Zoya", "Riya", "Meera"];
    show(friends[2]); (a) Aman (b) Kabir (c) Zoya (d) Riya
13. 13.💾 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
14. 14.Which of these fits saving in the cloud? (a) the sound on/off setting (b) a draft you are typing (c) notes to read offline (d) a shared to-do list
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.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
17. 17.💾 What number does this code show?
    let stars = 8;
    stars = stars - 6;
    stars = stars + 1;
    show(stars);
18. 18.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
19. 19.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
20. 20.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
21. 21.💾 Which works with no internet at all? (a) a cloud backup (b) a cloud leaderboard (c) a shared chat (d) data saved on the phone
22. 22.💾 What number does this code show?
    let coins = 7;
    coins = coins - 2;
    coins = coins + 5;
    show(coins);
23. 23.Which of these fits saving in the cloud? (a) a draft you are typing (b) chat messages to friends (c) notes to read offline (d) the sound on/off setting
24. 24.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
25. 25.💾 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
26. 26.💾 What number does this code show?
    let coins = 9;
    coins = coins - 3;
    coins = coins + 1;
    show(coins);
27. 27.💾 In most code, the first item of a list is at position ___. (a) 0 (b) 10 (c) 1 (d) 2
28. 28.💾 pop() takes off the last item. What does this code show?
    let friends = ["Zoya", "Riya", "Arjun"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Zoya (b) Arjun (c) Riya
29. 29.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Maths", "Art"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Maths (c) Science
30. 30.💾 pop() takes off the last item. What does this code show?
    let friends = ["Arjun", "Meera", "Zoya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Meera (b) Arjun (c) Zoya
31. 31.💾 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
32. 32.💾 What number does this code show?
    let friends = ["Arjun", "Riya"];
    friends.push("Aman");
    friends.push("Meera");
    show(friends.length);
33. 33.Which of these fits saving on the phone? (a) a shared to-do list (b) photos on two devices (c) the sound on/off setting (d) a class leaderboard
34. 34.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
35. 35.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
36. 36.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Art", "Hindi"];
    show(notes[0]); (a) Hindi (b) Art (c) Maths
37. 37.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Hindi", "Sports", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Sports (b) Maths (c) Music (d) Hindi
38. 38.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
39. 39.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Music", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Music (b) Sports (c) Science
40. 40.💾 What does this code show? (Positions start at 0.)
    let friends = ["Kabir", "Aman", "Meera", "Zoya"];
    show(friends[0]); (a) Meera (b) Kabir (c) Zoya (d) Aman

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