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App Dev Worksheet: If Else Rules

App development lesson 18: if / else: app rules · Set 629 · 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 = 15;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  2. 2.🔀 What does if / else let an app do? (a) draw a screen (b) pick one of two actions (c) save a photo (d) repeat forever
  3. 3.🔀 What does this PIN rule show?
    let pin = "15160";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  4. 4.🔀 What does this battery rule show?
    let battery = 43;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  5. 5.🔀 With if / else if / else, how many parts run? (a) only one (b) two (c) all of them (d) none
  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 sign-up rule show?
    let age = 8;
    if (age >= 13) {
      show("Welcome!");
    } else {
      show("Ask a parent");
    }
    (a) Ask a parent (b) Welcome!
  8. 8.🔀 In this course’s code, which sign tests “is equal to”? (a) !== (b) = (c) => (d) ===
  9. 9.🔀 When does the else part run? (a) when the test is false (b) always (c) when the test is true (d) never
  10. 10.🔀 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!
  11. 11.🔀 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
  12. 12.🔀 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
  13. 13.🔀 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) Gold (c) Silver
  14. 14.🔀 What does this battery rule show?
    let battery = 59;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  15. 15.🔀 What does this PIN rule show?
    let pin = "251";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  16. 16.🔀 What number does this shop app show?
    let total = 340;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  17. 17.🔀 What does >= mean? (a) not equal (b) greater than or equal (c) less than (d) smaller or equal
  18. 18.🔀 What does this battery rule show?
    let battery = 6;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  19. 19.🔀 What number does this shop app show?
    let total = 380;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  20. 20.🔀 What does this PIN rule show?
    let pin = "6495";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  21. 21.🔀 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) Bronze (c) Gold
  22. 22.🔀 What does this PIN rule show?
    let pin = "6142";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  23. 23.🔀 Which badge does this quiz app show?
    let marks = 100;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Silver (c) Bronze
  24. 24.🔀 What does this PIN rule show?
    let pin = "4444";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  25. 25.🔀 What does this PIN rule show?
    let pin = "573";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  26. 26.🔀 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
  27. 27.🔀 What number does this shop app show?
    let total = 230;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  28. 28.🔀 What does this PIN rule show?
    let pin = "77398";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) PIN saved (b) Use 4 digits
  29. 29.🔀 Which badge does this quiz app show?
    let marks = 72;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Bronze (c) Silver
  30. 30.🔀 What does this battery rule show?
    let battery = 12;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  31. 31.🔀 What does this battery rule show?
    let battery = 8;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Battery OK (b) Low battery
  32. 32.🔀 Which badge does this quiz app show?
    let marks = 96;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Bronze (b) Gold (c) Silver
  33. 33.🔀 Which badge does this quiz app show?
    let marks = 43;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Silver (b) Gold (c) Bronze
  34. 34.🔀 What does this PIN rule show?
    let pin = "35251";
    if (pin.length === 4) {
      show("PIN saved");
    } else {
      show("Use 4 digits");
    }
    (a) Use 4 digits (b) PIN saved
  35. 35.🔀 What number does this shop app show?
    let total = 890;
    if (total > 500) {
      total = total - 50;
    }
    show(total);
  36. 36.🔀 Which badge does this quiz app show?
    let marks = 31;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Bronze (c) Silver
  37. 37.🔀 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!
  38. 38.🔀 What does this battery rule show?
    let battery = 27;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK
  39. 39.🔀 Which badge does this quiz app show?
    let marks = 32;
    if (marks >= 80) {
      show("Gold");
    } else if (marks >= 50) {
      show("Silver");
    } else {
      show("Bronze");
    }
    (a) Gold (b) Bronze (c) Silver
  40. 40.🔀 What does this battery rule show?
    let battery = 75;
    if (battery < 20) {
      show("Low battery");
    } else {
      show("Battery OK");
    }
    (a) Low battery (b) Battery OK

Answer key

  1. Welcome!
  2. pick one of two actions
  3. Use 4 digits
  4. Battery OK
  5. only one
  6. Ask a parent
  7. Ask a parent
  8. ===
  9. when the test is false
  10. Welcome!
  11. Ask a parent
  12. Ask a parent
  13. Silver
  14. Battery OK
  15. Use 4 digits
  16. 340
  17. greater than or equal
  18. Low battery
  19. 380
  20. PIN saved
  21. Bronze
  22. PIN saved
  23. Gold
  24. PIN saved
  25. Use 4 digits
  26. Battery OK
  27. 230
  28. Use 4 digits
  29. Silver
  30. Low battery
  31. Low battery
  32. Gold
  33. Bronze
  34. Use 4 digits
  35. 840
  36. Bronze
  37. Welcome!
  38. Battery OK
  39. Bronze
  40. Battery OK

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