Knowledge check: Arrays, Objects and Functions in Javascript

What data type is the variable item ?
```
 var item = [];
```
- Boolean
- Function
- Array
What is the value of result for the following code?
```
 var result = "Hello".indexOf('l');
```
- 1
- 2
- 3
- 4

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');

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

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";

In the following function, the variables a and b are known as _______________.
```
 function add(a, b) {
       return a + b;
 }
```
- Parameters
- Return Values
Which of the following are functions of the Math object?
- random()
- round()
- sqrt()
- trim()

Knowledge check: Arrays, Objects and Functions in Javascript

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