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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 666 · 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.🔀 When does the else part run? (a) when the test is true (b) always (c) when the test is false (d) never
  2. 2.🔀 What does this PIN rule show?
    let pin = "3546";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  3. 3.🔀 What does this battery rule show?
    let battery = 59;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  4. 4.🔀 What does this sign-up rule show?
    let age = 13;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  5. 5.🔀 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
  6. 6.🔀 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
  7. 7.🔀 What does this battery rule show?
    let battery = 3;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  8. 8.🔀 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
  9. 9.🔀 What number does this shop app show?
    let total = 400;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  10. 10.🔀 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
  11. 11.🔀 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) Gold (c) Bronze
  12. 12.🔀 What number does this shop app show?
    let total = 480;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  13. 13.🔀 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
  14. 14.🔀 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
  15. 15.🔀 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
  16. 16.🔀 With if / else if / else, how many parts run? (a) two (b) only one (c) none (d) all of them
  17. 17.🔀 Which badge does this quiz app show?
    let marks = 60;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Bronze (c) Silver
  18. 18.🔀 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!
  19. 19.🔀 What does this PIN rule show?
    let pin = "6306";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  20. 20.🔀 What does this battery rule show?
    let battery = 76;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  21. 21.🔀 What number does this shop app show?
    let total = 740;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  22. 22.🔀 What does this battery rule show?
    let battery = 31;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  23. 23.🔀 What does >= mean? (a) less than (b) greater than or equal (c) smaller or equal (d) not equal
  24. 24.🔀 What does this battery rule show?
    let battery = 72;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  25. 25.🔀 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
  26. 26.🔀 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
  27. 27.🔀 Which badge does this quiz app show?
    let marks = 98;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Bronze (c) Gold
  28. 28.🔀 What does this battery rule show?
    let battery = 84;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  29. 29.🔀 What number does this shop app show?
    let total = 200;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  30. 30.🔀 Which badge does this quiz app show?
    let marks = 21;
    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 = 79;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  32. 32.🔀 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!
  33. 33.🔀 In this course’s code, which sign tests “is equal to”? (a) => (b) === (c) !== (d) =
  34. 34.🔀 What number does this shop app show?
    let total = 310;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  35. 35.🔀 What number does this shop app show?
    let total = 590;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  36. 36.🔀 What number does this shop app show?
    let total = 820;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  37. 37.🔀 What does this battery rule show?
    let battery = 98;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  38. 38.🔀 Which badge does this quiz app show?
    let marks = 89;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Gold (c) Bronze
  39. 39.🔀 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) Silver (b) Bronze (c) Gold
  40. 40.🔀 What does this battery rule show?
    let battery = 58;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery

Answer key

  1. when the test is false
  2. PIN saved
  3. Battery OK
  4. Welcome!
  5. pick one of two actions
  6. Ask a parent
  7. Low battery
  8. Ask a parent
  9. 400
  10. Bronze
  11. Bronze
  12. 480
  13. Welcome!
  14. Battery OK
  15. Battery OK
  16. only one
  17. Silver
  18. Ask a parent
  19. PIN saved
  20. Battery OK
  21. 690
  22. Battery OK
  23. greater than or equal
  24. Battery OK
  25. Ask a parent
  26. Ask a parent
  27. Gold
  28. Battery OK
  29. 200
  30. Bronze
  31. Battery OK
  32. Welcome!
  33. ===
  34. 310
  35. 540
  36. 770
  37. Battery OK
  38. Gold
  39. Silver
  40. Battery OK

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