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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 92 · 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 = 95;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  2. 2.🔀 What does this PIN rule show?
    let pin = "2118";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  3. 3.🔀 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
  4. 4.🔀 What number does this shop app show?
    let total = 730;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  5. 5.🔀 With if / else if / else, how many parts run? (a) all of them (b) none (c) two (d) only one
  6. 6.🔀 What does if / else let an app do? (a) draw a screen (b) repeat forever (c) save a photo (d) pick one of two actions
  7. 7.🔀 What number does this shop app show?
    let total = 500;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  8. 8.🔀 What does this PIN rule show?
    let pin = "9541";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) Use 4 digits (b) PIN saved
  9. 9.🔀 Which badge does this quiz app show?
    let marks = 91;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Silver (b) Gold (c) Bronze
  10. 10.🔀 In this course’s code, which sign tests “is equal to”? (a) => (b) !== (c) = (d) ===
  11. 11.🔀 When does the else part run? (a) never (b) when the test is true (c) when the test is false (d) always
  12. 12.🔀 What number does this shop app show?
    let total = 670;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  13. 13.🔀 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) Silver (b) Bronze (c) Gold
  14. 14.🔀 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
  15. 15.🔀 What number does this shop app show?
    let total = 850;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  16. 16.🔀 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
  17. 17.🔀 What number does this shop app show?
    let total = 510;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  18. 18.🔀 What number does this shop app show?
    let total = 880;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  19. 19.🔀 What number does this shop app show?
    let total = 440;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  20. 20.🔀 What does this battery rule show?
    let battery = 22;
    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 = 480;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  22. 22.🔀 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
  23. 23.🔀 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
  24. 24.🔀 What does this PIN rule show?
    let pin = "77362";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  25. 25.🔀 What does this PIN rule show?
    let pin = "39983";
    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 = 90;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }     (a) Gold (b) Bronze (c) Silver
  27. 27.🔀 What does >= mean? (a) smaller or equal (b) greater than or equal (c) not equal (d) less than
  28. 28.🔀 What number does this shop app show?
    let total = 660;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  29. 29.🔀 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
  30. 30.🔀 What does this battery rule show?
    let battery = 64;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }     (a) Low battery (b) Battery OK
  31. 31.🔀 What does this battery rule show?
    let battery = 20;
    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 = 570;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  33. 33.🔀 What number does this shop app show?
    let total = 770;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  34. 34.🔀 What does this PIN rule show?
    let pin = "20190";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  35. 35.🔀 What number does this shop app show?
    let total = 450;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  36. 36.🔀 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
  37. 37.🔀 What number does this shop app show?
    let total = 400;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  38. 38.🔀 What number does this shop app show?
    let total = 620;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  39. 39.🔀 What does this PIN rule show?
    let pin = "273";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }     (a) PIN saved (b) Use 4 digits
  40. 40.🔀 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!

Answer key

  1. Battery OK
  2. PIN saved
  3. Low battery
  4. 680
  5. only one
  6. pick one of two actions
  7. 500
  8. PIN saved
  9. Gold
  10. ===
  11. when the test is false
  12. 620
  13. Silver
  14. Battery OK
  15. 800
  16. Ask a parent
  17. 460
  18. 830
  19. 440
  20. Battery OK
  21. 480
  22. Battery OK
  23. Ask a parent
  24. Use 4 digits
  25. Use 4 digits
  26. Gold
  27. greater than or equal
  28. 610
  29. Welcome!
  30. Battery OK
  31. Battery OK
  32. 520
  33. 720
  34. Use 4 digits
  35. 450
  36. Battery OK
  37. 400
  38. 570
  39. Use 4 digits
  40. Welcome!

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