Below is an instruction that describes a task. Write a response that appropriately completes the request.

### Instruction:
How many of the episodes in the top 50 rankings were originally aired on June 28, 2010?

### Inputs:
table_name: table, columns: ['Episode number', 'Title', 'Original airing', 'Timeslot', 'Viewers', 'Top 50 Ranking', 'Scripted Show Ranking']

### Response:
SELECT COUNT Top 50 Ranking FROM table WHERE Original airing = June 28, 2010