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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 796 · 40 questions
TalentJR

Developer's tip (Test, then choose): if (test) { A } else { B }: A runs when the test is true, B when it is false. else if: check from the top; the first true test wins and the rest are skipped. >= includes the number itself; > does not. === tests “is equal to”.

NameDateTime takenScore ___ / 40
  1. 1.🔀 What does this battery rule show?
    let battery = 3;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  2. 2.🔀 What does this PIN rule show?
    let pin = "8664";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  3. 3.🔀 What does this PIN rule show?
    let pin = "25882";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  4. 4.🔀 What does this battery rule show?
    let battery = 43;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  5. 5.🔀 In this course’s code, which sign tests “is equal to”? (a) === (b) !== (c) = (d) =>
  6. 6.🔀 Which badge does this quiz app show?
    let marks = 55;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Bronze (c) Silver
  7. 7.🔀 What does this battery rule show?
    let battery = 30;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  8. 8.🔀 What does this PIN rule show?
    let pin = "511";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  9. 9.🔀 When does the else part run? (a) always (b) when the test is true (c) never (d) when the test is false
  10. 10.🔀 With if / else if / else, how many parts run? (a) all of them (b) none (c) two (d) only one
  11. 11.🔀 What does this PIN rule show?
    let pin = "75404";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  12. 12.🔀 What number does this shop app show?
    let total = 610;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  13. 13.🔀 Which badge does this quiz app show?
    let marks = 45;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Silver (c) Gold
  14. 14.🔀 What does this battery rule show?
    let battery = 18;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  15. 15.🔀 What does this PIN rule show?
    let pin = "5431";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  16. 16.🔀 What does this sign-up rule show?
    let age = 11;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  17. 17.🔀 Which badge does this quiz app show?
    let marks = 90;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Bronze (c) Gold
  18. 18.🔀 What does this battery rule show?
    let battery = 49;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  19. 19.🔀 What does this battery rule show?
    let battery = 47;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  20. 20.🔀 What does if / else let an app do? (a) repeat forever (b) draw a screen (c) pick one of two actions (d) save a photo
  21. 21.🔀 What does this sign-up rule show?
    let age = 13;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  22. 22.🔀 What number does this shop app show?
    let total = 870;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  23. 23.🔀 What number does this shop app show?
    let total = 350;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  24. 24.🔀 What does this battery rule show?
    let battery = 20;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  25. 25.🔀 What does this battery rule show?
    let battery = 17;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  26. 26.🔀 What does this battery rule show?
    let battery = 70;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  27. 27.🔀 What number does this shop app show?
    let total = 240;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  28. 28.🔀 What does this PIN rule show?
    let pin = "838";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  29. 29.🔀 What does this PIN rule show?
    let pin = "357";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  30. 30.🔀 What does this battery rule show?
    let battery = 28;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  31. 31.🔀 What number does this shop app show?
    let total = 840;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  32. 32.🔀 What does this sign-up rule show?
    let age = 8;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  33. 33.🔀 What number does this shop app show?
    let total = 320;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  34. 34.🔀 What does this sign-up rule show?
    let age = 16;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  35. 35.🔀 What does >= mean? (a) not equal (b) smaller or equal (c) less than (d) greater than or equal
  36. 36.🔀 What does this PIN rule show?
    let pin = "3927";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  37. 37.🔀 Which badge does this quiz app show?
    let marks = 60;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Bronze (c) Silver
  38. 38.🔀 What does this sign-up rule show?
    let age = 9;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  39. 39.🔀 Which badge does this quiz app show?
    let marks = 89;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Gold (c) Silver
  40. 40.🔀 What does this PIN rule show?
    let pin = "179";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved

Answer key

  1. Low battery
  2. PIN saved
  3. Use 4 digits
  4. Battery OK
  5. ===
  6. Silver
  7. Battery OK
  8. Use 4 digits
  9. when the test is false
  10. only one
  11. Use 4 digits
  12. 560
  13. Bronze
  14. Low battery
  15. PIN saved
  16. Ask a parent
  17. Gold
  18. Battery OK
  19. Battery OK
  20. pick one of two actions
  21. Welcome!
  22. 820
  23. 350
  24. Battery OK
  25. Low battery
  26. Battery OK
  27. 240
  28. Use 4 digits
  29. Use 4 digits
  30. Battery OK
  31. 790
  32. Ask a parent
  33. 320
  34. Welcome!
  35. greater than or equal
  36. PIN saved
  37. Silver
  38. Ask a parent
  39. Gold
  40. Use 4 digits

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