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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 452 · 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 battery rule show?
    let battery = 85;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  2. 2.🔀 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
  3. 3.🔀 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
  4. 4.🔀 Which badge does this quiz app show?
    let marks = 29;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Gold (c) Bronze
  5. 5.🔀 When does the else part run? (a) when the test is true (b) when the test is false (c) always (d) never
  6. 6.🔀 In this course’s code, which sign tests “is equal to”? (a) = (b) => (c) === (d) !==
  7. 7.🔀 What does this battery rule show?
    let battery = 27;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  8. 8.🔀 What number does this shop app show?
    let total = 690;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  9. 9.🔀 With if / else if / else, how many parts run? (a) two (b) only one (c) none (d) all of them
  10. 10.🔀 What number does this shop app show?
    let total = 790;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  11. 11.🔀 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
  12. 12.🔀 What does >= mean? (a) not equal (b) smaller or equal (c) greater than or equal (d) less than
  13. 13.🔀 Which badge does this quiz app show?
    let marks = 88;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Gold (c) Bronze
  14. 14.🔀 What number does this shop app show?
    let total = 390;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  15. 15.🔀 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!
  16. 16.🔀 What number does this shop app show?
    let total = 420;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  17. 17.🔀 What number does this shop app show?
    let total = 210;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  18. 18.🔀 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
  19. 19.🔀 What does if / else let an app do? (a) pick one of two actions (b) draw a screen (c) save a photo (d) repeat forever
  20. 20.🔀 What does this battery rule show?
    let battery = 81;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  21. 21.🔀 What does this battery rule show?
    let battery = 93;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  22. 22.🔀 What does this battery rule show?
    let battery = 57;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  23. 23.🔀 Which badge does this quiz app show?
    let marks = 56;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Silver (c) Gold
  24. 24.🔀 Which badge does this quiz app show?
    let marks = 30;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Silver (c) Gold
  25. 25.🔀 What does this sign-up rule show?
    let age = 17;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  26. 26.🔀 What does this battery rule show?
    let battery = 16;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  27. 27.🔀 What number does this shop app show?
    let total = 370;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  28. 28.🔀 What does this PIN rule show?
    let pin = "9234";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  29. 29.🔀 What does this PIN rule show?
    let pin = "2116";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  30. 30.🔀 What number does this shop app show?
    let total = 280;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  31. 31.🔀 What does this PIN rule show?
    let pin = "8484";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  32. 32.🔀 What does this PIN rule show?
    let pin = "236";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  33. 33.🔀 What number does this shop app show?
    let total = 780;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  34. 34.🔀 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
  35. 35.🔀 Which badge does this quiz app show?
    let marks = 64;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Silver (c) Gold
  36. 36.🔀 What does this battery rule show?
    let battery = 94;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  37. 37.🔀 What number does this shop app show?
    let total = 350;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  38. 38.🔀 What does this PIN rule show?
    let pin = "91137";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  39. 39.🔀 What does this battery rule show?
    let battery = 77;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  40. 40.🔀 What does this PIN rule show?
    let pin = "316";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved

Answer key

  1. Battery OK
  2. Ask a parent
  3. Low battery
  4. Bronze
  5. when the test is false
  6. ===
  7. Battery OK
  8. 640
  9. only one
  10. 740
  11. Welcome!
  12. greater than or equal
  13. Gold
  14. 390
  15. Ask a parent
  16. 420
  17. 210
  18. Ask a parent
  19. pick one of two actions
  20. Battery OK
  21. Battery OK
  22. Battery OK
  23. Silver
  24. Bronze
  25. Welcome!
  26. Low battery
  27. 370
  28. PIN saved
  29. PIN saved
  30. 280
  31. PIN saved
  32. Use 4 digits
  33. 730
  34. Low battery
  35. Silver
  36. Battery OK
  37. 350
  38. Use 4 digits
  39. Battery OK
  40. Use 4 digits

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