David Nguyen
Knowledge check: Arrays, Objects and Functions in Javascript

Knowledge check: Arrays, Objects and Functions in Javascript

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David Nguyen
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1 min read

  1. What data type is the variable item ?

     var item = [];

    • Boolean

    • Function

    • Array

  2. What is the value of result for the following code?

     var result = "Hello".indexOf('l');

    • 1

    • 2

    • 3

    • 4

  3. What is the length of the clothes array after this code runs?

     var clothes = [];
   clothes.push('gray t-shirt');
   clothes.push('green scarf');
   clothes.pop();
   clothes.push('slippers');
   clothes.pop();
   clothes.push('boots');
   clothes.push('old jeans');

    • 1

    • 2

    • 3

    • 4

  4. What value is printed out by the following code?

     var food = [];
 food.push('Chocolate');
 food.push('Ice cream');
 food.push('Donut');

 console.log(food[1])

    • Chocolate

    • Ice cream

    • Donut

  5. How many properties does the dog object have after the following code is run?

     var dog = {
     color: "brown",
     height: 30,
     length: 60
 };
 dog["type"] = "corgi";

    • 1

    • 2

    • 3

    • 4

  6. In the following function, the variables a and b are known as _______________.

     function add(a, b) {
       return a + b;
 }

    • Parameters

    • Return Values

  7. Which of the following are functions of the Math object?

    • random()

    • round()

    • sqrt()

    • trim()