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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 270 · 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 = 8;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }     (a) Ask a parent (b) Welcome!
  2. 2.🔀 What does this sign-up rule show?
    let age = 10;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }     (a) Welcome! (b) Ask a parent
  3. 3.🔀 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!
  4. 4.🔀 With if / else if / else, how many parts run? (a) none (b) all of them (c) two (d) only one
  5. 5.🔀 What does this PIN rule show?
    let pin = "9411";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  6. 6.🔀 What number does this shop app show?
    let total = 620;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  7. 7.🔀 What number does this shop app show?
    let total = 330;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  8. 8.🔀 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!
  9. 9.🔀 What number does this shop app show?
    let total = 220;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  10. 10.🔀 What does if / else let an app do? (a) repeat forever (b) pick one of two actions (c) save a photo (d) draw a screen
  11. 11.🔀 What does this PIN rule show?
    let pin = "75658";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  12. 12.🔀 In this course’s code, which sign tests “is equal to”? (a) = (b) !== (c) === (d) =>
  13. 13.🔀 When does the else part run? (a) never (b) when the test is true (c) always (d) when the test is false
  14. 14.🔀 What does this battery rule show?
    let battery = 46;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Battery OK (b) Low battery
  15. 15.🔀 What number does this shop app show?
    let total = 830;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  16. 16.🔀 Which badge does this quiz app show?
    let marks = 67;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Silver (b) Bronze (c) Gold
  17. 17.🔀 What does this battery rule show?
    let battery = 10;
    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 = 29;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Battery OK (b) Low battery
  19. 19.🔀 What number does this shop app show?
    let total = 570;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  20. 20.🔀 What does this PIN rule show?
    let pin = "899";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  21. 21.🔀 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
  22. 22.🔀 What number does this shop app show?
    let total = 860;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  23. 23.🔀 What number does this shop app show?
    let total = 470;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  24. 24.🔀 What does >= mean? (a) not equal (b) less than (c) greater than or equal (d) smaller or equal
  25. 25.🔀 What does this battery rule show?
    let battery = 31;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  26. 26.🔀 What does this PIN rule show?
    let pin = "1349";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  27. 27.🔀 Which badge does this quiz app show?
    let marks = 50;
    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 sign-up rule show?
    let age = 11;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }     (a) Ask a parent (b) Welcome!
  29. 29.🔀 What number does this shop app show?
    let total = 410;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  30. 30.🔀 What does this PIN rule show?
    let pin = "814";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  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 = 730;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  33. 33.🔀 What does this battery rule show?
    let battery = 13;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  34. 34.🔀 What does this battery rule show?
    let battery = 14;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  35. 35.🔀 What number does this shop app show?
    let total = 790;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  36. 36.🔀 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
  37. 37.🔀 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
  38. 38.🔀 Which badge does this quiz app show?
    let marks = 76;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Bronze (b) Silver (c) Gold
  39. 39.🔀 What does this PIN rule show?
    let pin = "674";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  40. 40.🔀 What does this PIN rule show?
    let pin = "7017";
    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. Ask a parent
  3. Welcome!
  4. only one
  5. PIN saved
  6. 570
  7. 330
  8. Ask a parent
  9. 220
  10. pick one of two actions
  11. Use 4 digits
  12. ===
  13. when the test is false
  14. Battery OK
  15. 780
  16. Silver
  17. Low battery
  18. Battery OK
  19. 520
  20. Use 4 digits
  21. Battery OK
  22. 810
  23. 470
  24. greater than or equal
  25. Battery OK
  26. PIN saved
  27. Silver
  28. Ask a parent
  29. 410
  30. Use 4 digits
  31. Battery OK
  32. 680
  33. Low battery
  34. Low battery
  35. 740
  36. Bronze
  37. Low battery
  38. Silver
  39. Use 4 digits
  40. PIN saved

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