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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 564 · 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.🔀 When does the else part run? (a) always (b) never (c) when the test is false (d) when the test is true
  2. 2.🔀 In this course’s code, which sign tests “is equal to”? (a) => (b) !== (c) === (d) =
  3. 3.🔀 What does this PIN rule show?
    let pin = "9297";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  4. 4.🔀 What does if / else let an app do? (a) draw a screen (b) save a photo (c) repeat forever (d) pick one of two actions
  5. 5.🔀 What number does this shop app show?
    let total = 440;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  6. 6.🔀 Which badge does this quiz app show?
    let marks = 78;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Gold (b) Silver (c) Bronze
  7. 7.🔀 What does this battery rule show?
    let battery = 91;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  8. 8.🔀 What does this PIN rule show?
    let pin = "31439";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  9. 9.🔀 With if / else if / else, how many parts run? (a) only one (b) none (c) all of them (d) two
  10. 10.🔀 What does this battery rule show?
    let battery = 2;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Battery OK (b) Low battery
  11. 11.🔀 What does >= mean? (a) less than (b) smaller or equal (c) greater than or equal (d) not equal
  12. 12.🔀 What number does this shop app show?
    let total = 840;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  13. 13.🔀 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) Silver (b) Bronze (c) Gold
  14. 14.🔀 What does this battery rule show?
    let battery = 42;
    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 = 16;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Battery OK (b) Low battery
  16. 16.🔀 What number does this shop app show?
    let total = 300;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  17. 17.🔀 What does this PIN rule show?
    let pin = "7124";
    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 = 250;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  19. 19.🔀 What does this battery rule show?
    let battery = 89;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Battery OK (b) Low battery
  20. 20.🔀 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!
  21. 21.🔀 What number does this shop app show?
    let total = 340;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  22. 22.🔀 What does this PIN rule show?
    let pin = "222";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  23. 23.🔀 What number does this shop app show?
    let total = 490;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  24. 24.🔀 What does this battery rule show?
    let battery = 6;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Battery OK (b) Low battery
  25. 25.🔀 What number does this shop app show?
    let total = 350;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  26. 26.🔀 What number does this shop app show?
    let total = 270;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  27. 27.🔀 What number does this shop app show?
    let total = 580;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  28. 28.🔀 Which badge does this quiz app show?
    let marks = 68;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Silver (b) Gold (c) Bronze
  29. 29.🔀 What number does this shop app show?
    let total = 610;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  30. 30.🔀 What does this PIN rule show?
    let pin = "137";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  31. 31.🔀 What does this battery rule show?
    let battery = 53;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Battery OK (b) Low battery
  32. 32.🔀 What number does this shop app show?
    let total = 850;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  33. 33.🔀 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
  34. 34.🔀 What number does this shop app show?
    let total = 630;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  35. 35.🔀 What number does this shop app show?
    let total = 690;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  36. 36.🔀 What does this PIN rule show?
    let pin = "175";
    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 = 40;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Bronze (b) Silver (c) Gold
  38. 38.🔀 What does this PIN rule show?
    let pin = "41618";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  39. 39.🔀 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
  40. 40.🔀 What does this battery rule show?
    let battery = 3;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK

Answer key

  1. when the test is false
  2. ===
  3. PIN saved
  4. pick one of two actions
  5. 440
  6. Silver
  7. Battery OK
  8. Use 4 digits
  9. only one
  10. Low battery
  11. greater than or equal
  12. 790
  13. Bronze
  14. Battery OK
  15. Low battery
  16. 300
  17. PIN saved
  18. 250
  19. Battery OK
  20. Welcome!
  21. 340
  22. Use 4 digits
  23. 490
  24. Low battery
  25. 350
  26. 270
  27. 530
  28. Silver
  29. 560
  30. Use 4 digits
  31. Battery OK
  32. 800
  33. Welcome!
  34. 580
  35. 640
  36. Use 4 digits
  37. Bronze
  38. Use 4 digits
  39. Ask a parent
  40. Low battery

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