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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 905 · 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 = 13;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  2. 2.🔀 When does the else part run? (a) when the test is true (b) when the test is false (c) always (d) never
  3. 3.🔀 What does this battery rule show?
    let battery = 38;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  4. 4.🔀 What does this PIN rule show?
    let pin = "44973";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  5. 5.🔀 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!
  6. 6.🔀 What does this battery rule show?
    let battery = 88;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  7. 7.🔀 What does this battery rule show?
    let battery = 96;
    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 = "869";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  9. 9.🔀 What does if / else let an app do? (a) draw a screen (b) pick one of two actions (c) repeat forever (d) save a photo
  10. 10.🔀 What does this sign-up rule show?
    let age = 17;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  11. 11.🔀 What does this PIN rule show?
    let pin = "3276";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  12. 12.🔀 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
  13. 13.🔀 Which badge does this quiz app show?
    let marks = 35;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Bronze (c) Gold
  14. 14.🔀 What does >= mean? (a) less than (b) not equal (c) greater than or equal (d) smaller or equal
  15. 15.🔀 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) Bronze (b) Gold (c) Silver
  16. 16.🔀 In this course’s code, which sign tests “is equal to”? (a) => (b) === (c) !== (d) =
  17. 17.🔀 What does this sign-up rule show?
    let age = 15;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  18. 18.🔀 What does this battery rule show?
    let battery = 71;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  19. 19.🔀 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
  20. 20.🔀 What does this PIN rule show?
    let pin = "6457";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  21. 21.🔀 What number does this shop app show?
    let total = 280;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  22. 22.🔀 What does this PIN rule show?
    let pin = "29763";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  23. 23.🔀 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!
  24. 24.🔀 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!
  25. 25.🔀 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
  26. 26.🔀 What number does this shop app show?
    let total = 720;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  27. 27.🔀 What does this battery rule show?
    let battery = 92;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  28. 28.🔀 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
  29. 29.🔀 What number does this shop app show?
    let total = 560;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  30. 30.🔀 Which badge does this quiz app show?
    let marks = 26;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Bronze (c) Gold
  31. 31.🔀 What does this battery rule show?
    let battery = 8;
    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 = 480;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  33. 33.🔀 What does this PIN rule show?
    let pin = "119";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  34. 34.🔀 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
  35. 35.🔀 Which badge does this quiz app show?
    let marks = 39;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Gold (c) Bronze
  36. 36.🔀 What does this battery rule show?
    let battery = 4;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  37. 37.🔀 What does this sign-up rule show?
    let age = 11;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  38. 38.🔀 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
  39. 39.🔀 What does this battery rule show?
    let battery = 90;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  40. 40.🔀 What does this battery rule show?
    let battery = 87;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK

Answer key

  1. Welcome!
  2. when the test is false
  3. Battery OK
  4. Use 4 digits
  5. Welcome!
  6. Battery OK
  7. Battery OK
  8. Use 4 digits
  9. pick one of two actions
  10. Welcome!
  11. PIN saved
  12. Ask a parent
  13. Bronze
  14. greater than or equal
  15. Silver
  16. ===
  17. Welcome!
  18. Battery OK
  19. Low battery
  20. PIN saved
  21. 280
  22. Use 4 digits
  23. Welcome!
  24. Ask a parent
  25. Low battery
  26. 670
  27. Battery OK
  28. Ask a parent
  29. 510
  30. Bronze
  31. Low battery
  32. 480
  33. Use 4 digits
  34. Battery OK
  35. Bronze
  36. Low battery
  37. Ask a parent
  38. Battery OK
  39. Battery OK
  40. Battery OK

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