edited by Hupaul Camacho

1. What are the types of the following expressions and what do they evaluate to, and why?

• 17 // This is a number value, which evaluates to 17, because node just interprets it as a single number.
• 1 + 2 * 3 + 4 // This is an arithmetic operation between number values, and evaluates to 11 because of the order of operations.
• 800 / 80 / 8 // This is another arithmetic operation that uses division to evaluate to 1.25, a number value.
• 400 > 200 // This expression uses a comparison operator to return a boolean value, which in this case is true, because 400 IS greater than 200.
• 1 !== 1 // This expression contains another comparison operator that tests for inequality, and evaluates to false, because 1 is the same as 1
• true || false // The OR operator checks to see if one of two statements are true and in this case the left side is true, making this evaluate to true
• true && false // The AND operator is used to test for truthy values on BOTH sides of the operator, making this evaluate to false because of the false value on the right side
• 20 % 6 // This expression uses the modulo operator, and evaluates to 2 which is the remainder from dividing 20 by 6
• 'a' + 'b' // This expression uses the + operator to join or concatenate these two strings together, which evaluates to 'ab'

2. What will the following return?

• typeof 4 // It will return 'number'
• typeof 'hello' // It will return 'string'
• typeof true // It will return 'boolean'
• 2 === 1 || 3 === 4 // It will return false

3. Create a truth table for the expression A || B.

For reference, here is a truth table for the expression A && B:

|   A   |   B   | A && B |
| true  | true  | true  |
| false | true  | false |
| true  | false | false |
| false | false | false |

A || B Truth table

|   A   |   B   | A || B|
| false | false | false |
| false | true  | true  |
|  true | false | true  |
|  true |  true | true  |

4. Create a truth table for the expression !A && !B.

For reference, here is a truth table for the expression A && !B:

|   A   |   B   |   !B   | A && B |
| true  | true  | false  | false |
| false | true  | false  | false |
| true  | false | true   | true  |
| false | false |  true  | false |

5. Write a step-by-step evaluation for the following expression (remember order of operations): 2 + 3 * 2 + 1. For reference, here is a exp of a step-by-step evaluation:

1 + 2 + 3 + 4
    3 + 3 + 4
        6 + 4
            10

// 2 + 3 * 2 + 1 // 2 + 6 + 1 // 8 + 1 // 9

6. Write a step-by-step evaluation for the following expression (remember order of operations): 4 / 2 + 8 / 4.

// 4 / 2 + 8 / 4 // 2 + 8 / 4 // 2 + 2 // 4

7. Write a step-by-step evaluation for the following expression: 'ca' + 'ter' + 'pi' + 'llar'.

// 'ca' + 'ter' + 'pi' + 'llar' // 'cater' + 'pi' + 'llar' // 'caterpi' + 'llar' // 'caterpillar'

8. Write a step-by-step evaluation for the following expression: 2 * 4 === 8 && 'car' + 'pool' === 'carpool'.

// 2 * 4 === 8 && 'car' + 'pool' === 'carpool' // 8 === 8 && 'car' + 'pool' === 'carpool' // 8 === 8 && 'carpool' === 'carpool' // true