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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 78 · 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 PIN rule show?
    let pin = "7898";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  2. 2.🔀 What does this battery rule show?
    let battery = 62;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  3. 3.🔀 With if / else if / else, how many parts run? (a) only one (b) all of them (c) none (d) two
  4. 4.🔀 What does this battery rule show?
    let battery = 1;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  5. 5.🔀 When does the else part run? (a) always (b) when the test is false (c) when the test is true (d) never
  6. 6.🔀 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
  7. 7.🔀 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
  8. 8.🔀 What does this battery rule show?
    let battery = 21;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  9. 9.🔀 What number does this shop app show?
    let total = 280;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  10. 10.🔀 What does this PIN rule show?
    let pin = "9664";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  11. 11.🔀 What number does this shop app show?
    let total = 410;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  12. 12.🔀 What number does this shop app show?
    let total = 270;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  13. 13.🔀 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
  14. 14.🔀 What does this battery rule show?
    let battery = 2;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  15. 15.🔀 What number does this shop app show?
    let total = 510;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  16. 16.🔀 What does this PIN rule show?
    let pin = "54711";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  17. 17.🔀 What does >= mean? (a) greater than or equal (b) smaller or equal (c) not equal (d) less than
  18. 18.🔀 What does this battery rule show?
    let battery = 89;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  19. 19.🔀 Which badge does this quiz app show?
    let marks = 24;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Silver (c) Bronze
  20. 20.🔀 What does this battery rule show?
    let battery = 78;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  21. 21.🔀 What number does this shop app show?
    let total = 490;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  22. 22.🔀 What does this battery rule show?
    let battery = 67;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  23. 23.🔀 What does this battery rule show?
    let battery = 80;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  24. 24.🔀 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!
  25. 25.🔀 What does this PIN rule show?
    let pin = "65615";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  26. 26.🔀 Which badge does this quiz app show?
    let marks = 70;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Bronze (c) Silver
  27. 27.🔀 What does this PIN rule show?
    let pin = "32084";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  28. 28.🔀 In this course’s code, which sign tests “is equal to”? (a) = (b) !== (c) => (d) ===
  29. 29.🔀 What does this PIN rule show?
    let pin = "7442";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  30. 30.🔀 What does if / else let an app do? (a) repeat forever (b) save a photo (c) pick one of two actions (d) draw a screen
  31. 31.🔀 What does this PIN rule show?
    let pin = "2157";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  32. 32.🔀 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!
  33. 33.🔀 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
  34. 34.🔀 Which badge does this quiz app show?
    let marks = 69;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Silver (c) Bronze
  35. 35.🔀 What does this sign-up rule show?
    let age = 12;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  36. 36.🔀 What number does this shop app show?
    let total = 520;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  37. 37.🔀 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) Bronze (b) Silver (c) Gold
  38. 38.🔀 What does this sign-up rule show?
    let age = 16;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Welcome! (b) Ask a parent
  39. 39.🔀 What number does this shop app show?
    let total = 330;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  40. 40.🔀 What does this PIN rule show?
    let pin = "524";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits

Answer key

  1. PIN saved
  2. Battery OK
  3. only one
  4. Low battery
  5. when the test is false
  6. Ask a parent
  7. Low battery
  8. Battery OK
  9. 280
  10. PIN saved
  11. 410
  12. 270
  13. Battery OK
  14. Low battery
  15. 460
  16. Use 4 digits
  17. greater than or equal
  18. Battery OK
  19. Bronze
  20. Battery OK
  21. 490
  22. Battery OK
  23. Battery OK
  24. Welcome!
  25. Use 4 digits
  26. Silver
  27. Use 4 digits
  28. ===
  29. PIN saved
  30. pick one of two actions
  31. PIN saved
  32. Welcome!
  33. Low battery
  34. Silver
  35. Ask a parent
  36. 470
  37. Gold
  38. Welcome!
  39. 330
  40. Use 4 digits

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