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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 842 · 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 sign-up rule show?
    let age = 12;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  2. 2.🔀 What number does this shop app show?
    let total = 490;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  3. 3.🔀 What does this battery rule show?
    let battery = 23;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  4. 4.🔀 What does if / else let an app do? (a) draw a screen (b) repeat forever (c) save a photo (d) pick one of two actions
  5. 5.🔀 With if / else if / else, how many parts run? (a) all of them (b) only one (c) none (d) two
  6. 6.🔀 What does this battery rule show?
    let battery = 49;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  7. 7.🔀 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
  8. 8.🔀 When does the else part run? (a) always (b) when the test is false (c) never (d) when the test is true
  9. 9.🔀 What does this battery rule show?
    let battery = 11;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  10. 10.🔀 What does this battery rule show?
    let battery = 7;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  11. 11.🔀 What number does this shop app show?
    let total = 260;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  12. 12.🔀 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
  13. 13.🔀 Which badge does this quiz app show?
    let marks = 36;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Gold (c) Bronze
  14. 14.🔀 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
  15. 15.🔀 What does this sign-up rule show?
    let age = 11;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  16. 16.🔀 What does this PIN rule show?
    let pin = "1756";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  17. 17.🔀 What number does this shop app show?
    let total = 380;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  18. 18.🔀 What number does this shop app show?
    let total = 620;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  19. 19.🔀 What number does this shop app show?
    let total = 520;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  20. 20.🔀 What does this sign-up rule show?
    let age = 16;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  21. 21.🔀 What does >= mean? (a) not equal (b) less than (c) greater than or equal (d) smaller or equal
  22. 22.🔀 Which badge does this quiz app show?
    let marks = 63;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Gold (c) Silver
  23. 23.🔀 What does this PIN rule show?
    let pin = "24225";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  24. 24.🔀 What does this PIN rule show?
    let pin = "755";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  25. 25.🔀 What does this PIN rule show?
    let pin = "40072";
    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 = 15;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  27. 27.🔀 What does this PIN rule show?
    let pin = "1626";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  28. 28.🔀 Which badge does this quiz app show?
    let marks = 70;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Silver (c) Gold
  29. 29.🔀 What does this battery rule show?
    let battery = 37;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  30. 30.🔀 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
  31. 31.🔀 What does this PIN rule show?
    let pin = "7336";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  32. 32.🔀 What does this sign-up rule show?
    let age = 14;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  33. 33.🔀 In this course’s code, which sign tests “is equal to”? (a) !== (b) => (c) = (d) ===
  34. 34.🔀 What does this battery rule show?
    let battery = 39;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  35. 35.🔀 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) Gold (b) Bronze (c) Silver
  36. 36.🔀 Which badge does this quiz app show?
    let marks = 72;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Silver (c) Bronze
  37. 37.🔀 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) Bronze (b) Silver (c) Gold
  38. 38.🔀 What does this battery rule show?
    let battery = 95;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  39. 39.🔀 What does this battery rule show?
    let battery = 46;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  40. 40.🔀 What does this PIN rule show?
    let pin = "33519";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits

Answer key

  1. Ask a parent
  2. 490
  3. Battery OK
  4. pick one of two actions
  5. only one
  6. Battery OK
  7. Ask a parent
  8. when the test is false
  9. Low battery
  10. Low battery
  11. 260
  12. Low battery
  13. Bronze
  14. Ask a parent
  15. Ask a parent
  16. PIN saved
  17. 380
  18. 570
  19. 470
  20. Welcome!
  21. greater than or equal
  22. Silver
  23. Use 4 digits
  24. Use 4 digits
  25. Use 4 digits
  26. Low battery
  27. PIN saved
  28. Silver
  29. Battery OK
  30. Bronze
  31. PIN saved
  32. Welcome!
  33. ===
  34. Battery OK
  35. Gold
  36. Silver
  37. Bronze
  38. Battery OK
  39. Battery OK
  40. Use 4 digits

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