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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 665 · 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 = 59;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  2. 2.🔀 Which badge does this quiz app show?
    let marks = 62;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Bronze (c) Silver
  3. 3.🔀 What does this PIN rule show?
    let pin = "5874";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  4. 4.🔀 What does this battery rule show?
    let battery = 55;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  5. 5.🔀 What does this PIN rule show?
    let pin = "3690";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  6. 6.🔀 What does >= mean? (a) smaller or equal (b) less than (c) not equal (d) greater than or equal
  7. 7.🔀 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) Gold (b) Silver (c) Bronze
  8. 8.🔀 When does the else part run? (a) when the test is false (b) always (c) when the test is true (d) never
  9. 9.🔀 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) Silver (b) Bronze (c) Gold
  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 battery rule show?
    let battery = 98;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  12. 12.🔀 What does this battery rule show?
    let battery = 2;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  13. 13.🔀 Which badge does this quiz app show?
    let marks = 59;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Bronze (c) Silver
  14. 14.🔀 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
  15. 15.🔀 What does if / else let an app do? (a) pick one of two actions (b) repeat forever (c) draw a screen (d) save a photo
  16. 16.🔀 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
  17. 17.🔀 What does this PIN rule show?
    let pin = "6474";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  18. 18.🔀 What number does this shop app show?
    let total = 890;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  19. 19.🔀 In this course’s code, which sign tests “is equal to”? (a) = (b) === (c) !== (d) =>
  20. 20.🔀 What does this sign-up rule show?
    let age = 9;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  21. 21.🔀 What number does this shop app show?
    let total = 870;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  22. 22.🔀 What does this PIN rule show?
    let pin = "13208";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  23. 23.🔀 What number does this shop app show?
    let total = 340;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  24. 24.🔀 What does this battery rule show?
    let battery = 21;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  25. 25.🔀 What does this PIN rule show?
    let pin = "8954";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  26. 26.🔀 What does this battery rule show?
    let battery = 92;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  27. 27.🔀 What number does this shop app show?
    let total = 500;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  28. 28.🔀 What does this PIN rule show?
    let pin = "2464";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  29. 29.🔀 What number does this shop app show?
    let total = 360;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  30. 30.🔀 What does this PIN rule show?
    let pin = "63331";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  31. 31.🔀 What does this sign-up rule show?
    let age = 8;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  32. 32.🔀 What does this PIN rule show?
    let pin = "7570";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  33. 33.🔀 What does this PIN rule show?
    let pin = "5520";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  34. 34.🔀 Which badge does this quiz app show?
    let marks = 54;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Gold (c) Silver
  35. 35.🔀 Which badge does this quiz app show?
    let marks = 25;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Silver (c) Bronze
  36. 36.🔀 What number does this shop app show?
    let total = 230;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  37. 37.🔀 Which badge does this quiz app show?
    let marks = 23;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Bronze (c) Gold
  38. 38.🔀 What does this battery rule show?
    let battery = 62;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  39. 39.🔀 What does this battery rule show?
    let battery = 94;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  40. 40.🔀 What number does this shop app show?
    let total = 300;
    if (total > 500) {
      total = total - 50;
    }
    show(total);

Answer key

  1. Battery OK
  2. Silver
  3. PIN saved
  4. Battery OK
  5. PIN saved
  6. greater than or equal
  7. Bronze
  8. when the test is false
  9. Silver
  10. only one
  11. Battery OK
  12. Low battery
  13. Silver
  14. Ask a parent
  15. pick one of two actions
  16. Welcome!
  17. PIN saved
  18. 840
  19. ===
  20. Ask a parent
  21. 820
  22. Use 4 digits
  23. 340
  24. Battery OK
  25. PIN saved
  26. Battery OK
  27. 500
  28. PIN saved
  29. 360
  30. Use 4 digits
  31. Ask a parent
  32. PIN saved
  33. PIN saved
  34. Silver
  35. Bronze
  36. 230
  37. Bronze
  38. Battery OK
  39. Battery OK
  40. 300

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