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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 676 · 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.🔀 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) Silver (c) Gold
  2. 2.🔀 With if / else if / else, how many parts run? (a) only one (b) none (c) two (d) all of them
  3. 3.🔀 What does this PIN rule show?
    let pin = "351";
    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) pick one of two actions (c) save a photo (d) repeat forever
  5. 5.🔀 What does this battery rule show?
    let battery = 27;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  6. 6.🔀 What does this PIN rule show?
    let pin = "786";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  7. 7.🔀 Which badge does this quiz app show?
    let marks = 49;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Silver (b) Bronze (c) Gold
  8. 8.🔀 What does >= mean? (a) not equal (b) smaller or equal (c) greater than or equal (d) less than
  9. 9.🔀 What number does this shop app show?
    let total = 250;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  10. 10.🔀 What does this battery rule show?
    let battery = 4;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Battery OK (b) Low battery
  11. 11.🔀 What does this sign-up rule show?
    let age = 12;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }     (a) Welcome! (b) Ask a parent
  12. 12.🔀 What number does this shop app show?
    let total = 710;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  13. 13.🔀 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
  14. 14.🔀 What does this battery rule show?
    let battery = 29;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Battery OK (b) Low battery
  15. 15.🔀 What does this PIN rule show?
    let pin = "906";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  16. 16.🔀 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!
  17. 17.🔀 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!
  18. 18.🔀 What does this PIN rule show?
    let pin = "435";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  19. 19.🔀 When does the else part run? (a) always (b) when the test is true (c) when the test is false (d) never
  20. 20.🔀 What does this PIN rule show?
    let pin = "6396";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  21. 21.🔀 What does this PIN rule show?
    let pin = "396";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  22. 22.🔀 Which badge does this quiz app show?
    let marks = 79;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Silver (b) Gold (c) Bronze
  23. 23.🔀 Which badge does this quiz app show?
    let marks = 82;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Silver (b) Bronze (c) Gold
  24. 24.🔀 What does this battery rule show?
    let battery = 25;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  25. 25.🔀 What number does this shop app show?
    let total = 420;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  26. 26.🔀 Which badge does this quiz app show?
    let marks = 48;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Silver (b) Gold (c) Bronze
  27. 27.🔀 What does this PIN rule show?
    let pin = "873";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  28. 28.🔀 In this course’s code, which sign tests “is equal to”? (a) !== (b) => (c) = (d) ===
  29. 29.🔀 Which badge does this quiz app show?
    let marks = 33;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Bronze (b) Silver (c) Gold
  30. 30.🔀 What does this battery rule show?
    let battery = 50;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Battery OK (b) Low battery
  31. 31.🔀 What does this battery rule show?
    let battery = 14;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Battery OK (b) Low battery
  32. 32.🔀 What does this PIN rule show?
    let pin = "2836";
    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 = "1135";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  34. 34.🔀 What number does this shop app show?
    let total = 770;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  35. 35.🔀 What number does this shop app show?
    let total = 460;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  36. 36.🔀 Which badge does this quiz app show?
    let marks = 66;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Silver (b) Gold (c) Bronze
  37. 37.🔀 What does this PIN rule show?
    let pin = "3912";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  38. 38.🔀 What number does this shop app show?
    let total = 660;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  39. 39.🔀 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
  40. 40.🔀 What does this sign-up rule show?
    let age = 10;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }     (a) Ask a parent (b) Welcome!

Answer key

  1. Silver
  2. only one
  3. Use 4 digits
  4. pick one of two actions
  5. Battery OK
  6. Use 4 digits
  7. Bronze
  8. greater than or equal
  9. 250
  10. Low battery
  11. Ask a parent
  12. 660
  13. Ask a parent
  14. Battery OK
  15. Use 4 digits
  16. Welcome!
  17. Ask a parent
  18. Use 4 digits
  19. when the test is false
  20. PIN saved
  21. Use 4 digits
  22. Silver
  23. Gold
  24. Battery OK
  25. 420
  26. Bronze
  27. Use 4 digits
  28. ===
  29. Bronze
  30. Battery OK
  31. Low battery
  32. PIN saved
  33. PIN saved
  34. 720
  35. 460
  36. Silver
  37. PIN saved
  38. 610
  39. Low battery
  40. Ask a parent

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