Write the following sets in roster form :
{months of year whose names begin with a vowel}

Answer

To write the set of months of the year whose names begin with a vowel in roster form, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Months of the Year**:
The months of the year are January, February, March, April, May, June, July, August, September, October, November, and December.

2. **Determine Which Months Start with a Vowel**:
We need to find out which of these months start with a vowel (A, E, I, O, U).

3. **List the Months Starting with Vowels**:
- **April** starts with 'A' (which is a vowel).
- **August** starts with 'A' (which is a vowel).
- **October** starts with 'O' (which is a vowel).

4. **Write the Set in Roster Form**:
Now, we can write the set of months whose names begin with a vowel in roster form. The roster form lists the elements of the set within curly braces.
- The set can be written as:
\[ A = \{ \text{April}, \text{August}, \text{October} \} \]

### Final Answer:
The set of months of the year whose names begin with a vowel in roster form is:
\[ A = \{ \text{April}, \text{August}, \text{October} \} \]