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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 753 · 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 = 87;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  2. 2.🔀 What does this sign-up rule show?
    let age = 10;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  3. 3.🔀 What does >= mean? (a) smaller or equal (b) less than (c) not equal (d) greater than or equal
  4. 4.🔀 Which badge does this quiz app show?
    let marks = 20;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Bronze (c) Gold
  5. 5.🔀 What number does this shop app show?
    let total = 370;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  6. 6.🔀 What number does this shop app show?
    let total = 650;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  7. 7.🔀 What does this battery rule show?
    let battery = 61;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  8. 8.🔀 What number does this shop app show?
    let total = 820;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  9. 9.🔀 What does this sign-up rule show?
    let age = 13;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  10. 10.🔀 What number does this shop app show?
    let total = 450;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  11. 11.🔀 Which badge does this quiz app show?
    let marks = 56;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Silver (c) Gold
  12. 12.🔀 Which badge does this quiz app show?
    let marks = 34;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Gold (c) Bronze
  13. 13.🔀 What number does this shop app show?
    let total = 850;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  14. 14.🔀 What does this battery rule show?
    let battery = 46;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  15. 15.🔀 What does this battery rule show?
    let battery = 63;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  16. 16.🔀 Which badge does this quiz app show?
    let marks = 38;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Gold (c) Silver
  17. 17.🔀 What does this battery rule show?
    let battery = 18;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  18. 18.🔀 What number does this shop app show?
    let total = 800;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  19. 19.🔀 What does if / else let an app do? (a) save a photo (b) pick one of two actions (c) repeat forever (d) draw a screen
  20. 20.🔀 What does this sign-up rule show?
    let age = 14;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  21. 21.🔀 What does this battery rule show?
    let battery = 29;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  22. 22.🔀 What does this PIN rule show?
    let pin = "6521";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  23. 23.🔀 What does this battery rule show?
    let battery = 48;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  24. 24.🔀 What does this sign-up rule show?
    let age = 15;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  25. 25.🔀 Which badge does this quiz app show?
    let marks = 41;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Bronze (c) Silver
  26. 26.🔀 What does this battery rule show?
    let battery = 10;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  27. 27.🔀 When does the else part run? (a) never (b) always (c) when the test is true (d) when the test is false
  28. 28.🔀 With if / else if / else, how many parts run? (a) none (b) all of them (c) two (d) only one
  29. 29.🔀 What number does this shop app show?
    let total = 310;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  30. 30.🔀 What number does this shop app show?
    let total = 360;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  31. 31.🔀 What does this PIN rule show?
    let pin = "62062";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  32. 32.🔀 In this course’s code, which sign tests “is equal to”? (a) === (b) = (c) !== (d) =>
  33. 33.🔀 What number does this shop app show?
    let total = 410;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  34. 34.🔀 What does this PIN rule show?
    let pin = "3203";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  35. 35.🔀 Which badge does this quiz app show?
    let marks = 24;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Bronze (c) Silver
  36. 36.🔀 What does this PIN rule show?
    let pin = "365";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  37. 37.🔀 What does this battery rule show?
    let battery = 19;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  38. 38.🔀 What does this battery rule show?
    let battery = 35;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  39. 39.🔀 What does this PIN rule show?
    let pin = "595";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  40. 40.🔀 What does this PIN rule show?
    let pin = "33661";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits

Answer key

  1. Battery OK
  2. Ask a parent
  3. greater than or equal
  4. Bronze
  5. 370
  6. 600
  7. Battery OK
  8. 770
  9. Welcome!
  10. 450
  11. Silver
  12. Bronze
  13. 800
  14. Battery OK
  15. Battery OK
  16. Bronze
  17. Low battery
  18. 750
  19. pick one of two actions
  20. Welcome!
  21. Battery OK
  22. PIN saved
  23. Battery OK
  24. Welcome!
  25. Bronze
  26. Low battery
  27. when the test is false
  28. only one
  29. 310
  30. 360
  31. Use 4 digits
  32. ===
  33. 410
  34. PIN saved
  35. Bronze
  36. Use 4 digits
  37. Low battery
  38. Battery OK
  39. Use 4 digits
  40. Use 4 digits

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