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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 46 · 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 if / else let an app do? (a) draw a screen (b) save a photo (c) pick one of two actions (d) repeat forever
  2. 2.🔀 What does >= mean? (a) not equal (b) less than (c) smaller or equal (d) greater than or equal
  3. 3.🔀 What does this battery rule show?
    let battery = 28;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Battery OK (b) Low battery
  4. 4.🔀 When does the else part run? (a) never (b) when the test is true (c) always (d) when the test is false
  5. 5.🔀 With if / else if / else, how many parts run? (a) only one (b) all of them (c) none (d) two
  6. 6.🔀 What does this battery rule show?
    let battery = 40;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  7. 7.🔀 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!
  8. 8.🔀 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!
  9. 9.🔀 What does this PIN rule show?
    let pin = "2017";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  10. 10.🔀 What does this PIN rule show?
    let pin = "58398";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  11. 11.🔀 What does this PIN rule show?
    let pin = "971";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  12. 12.🔀 Which badge does this quiz app show?
    let marks = 81;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Gold (b) Silver (c) Bronze
  13. 13.🔀 What number does this shop app show?
    let total = 290;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  14. 14.🔀 What does this PIN rule show?
    let pin = "7245";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  15. 15.🔀 What does this battery rule show?
    let battery = 45;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  16. 16.🔀 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!
  17. 17.🔀 What does this battery rule show?
    let battery = 64;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Battery OK (b) Low battery
  18. 18.🔀 What does this battery rule show?
    let battery = 41;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  19. 19.🔀 Which badge does this quiz app show?
    let marks = 44;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Gold (b) Silver (c) Bronze
  20. 20.🔀 Which badge does this quiz app show?
    let marks = 37;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Gold (b) Silver (c) Bronze
  21. 21.🔀 What number does this shop app show?
    let total = 720;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  22. 22.🔀 Which badge does this quiz app show?
    let marks = 73;
    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 = "2245";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  24. 24.🔀 What does this battery rule show?
    let battery = 16;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  25. 25.🔀 What does this battery rule show?
    let battery = 35;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  26. 26.🔀 Which badge does this quiz app show?
    let marks = 31;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Gold (b) Bronze (c) Silver
  27. 27.🔀 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) Bronze (b) Silver (c) Gold
  28. 28.🔀 What does this PIN rule show?
    let pin = "151";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  29. 29.🔀 What does this battery rule show?
    let battery = 8;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  30. 30.🔀 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
  31. 31.🔀 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
  32. 32.🔀 Which badge does this quiz app show?
    let marks = 22;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Gold (b) Bronze (c) Silver
  33. 33.🔀 What does this battery rule show?
    let battery = 66;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  34. 34.🔀 In this course’s code, which sign tests “is equal to”? (a) !== (b) === (c) = (d) =>
  35. 35.🔀 What number does this shop app show?
    let total = 530;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  36. 36.🔀 What does this sign-up rule show?
    let age = 8;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }     (a) Ask a parent (b) Welcome!
  37. 37.🔀 What does this PIN rule show?
    let pin = "2405";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  38. 38.🔀 What does this PIN rule show?
    let pin = "359";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  39. 39.🔀 What does this PIN rule show?
    let pin = "6306";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  40. 40.🔀 What number does this shop app show?
    let total = 460;
    if (total > 500) {
      total = total - 50;
    }
    show(total);

Answer key

  1. pick one of two actions
  2. greater than or equal
  3. Battery OK
  4. when the test is false
  5. only one
  6. Battery OK
  7. Welcome!
  8. Ask a parent
  9. PIN saved
  10. Use 4 digits
  11. Use 4 digits
  12. Gold
  13. 290
  14. PIN saved
  15. Battery OK
  16. Ask a parent
  17. Battery OK
  18. Battery OK
  19. Bronze
  20. Bronze
  21. 670
  22. Silver
  23. PIN saved
  24. Low battery
  25. Battery OK
  26. Bronze
  27. Silver
  28. Use 4 digits
  29. Low battery
  30. Welcome!
  31. Silver
  32. Bronze
  33. Battery OK
  34. ===
  35. 480
  36. Ask a parent
  37. PIN saved
  38. Use 4 digits
  39. PIN saved
  40. 460

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