Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Episode # | Title | Airdate | Rating (Millions) | Rank |
| --- | --- | --- | --- | --- |
| 1.0 | "Pilot (aka I Am Not Going to Sell Herbalux)" | January 5, 2007 | 4.89m | #4 |
| 2.0 | "The Box and the Bunny" | January 12, 2007 | 3.53m | #13 |
| 3.0 | "Queens for a Day" | January 19, 2007 | 5.27m | #5 |
| 4.0 | "Swag" | March 23, 2007 | 2.20m | #16 |
| 5.0 | "Fey's Sleigh Ride" | January 26, 2007 | 4.07m | #9 |
| 6.0 | "The Lyin', the Watch and the Wardrobe" | February 2, 2007 | 3.42m | #8 |
| 7.0 | "Trust, Lust, and Must" | February 9, 2007 | 3.30m | #10 |
| 8.0 | "After Hours" | February 16, 2007 | 3.12m | #8 |
| 9.0 | "Four Thanksgivings and a Funeral" | February 23, 2007 | 3.32m | #3 |
| 10.0 | "Lose the Boss" | March 2, 2007 | 2.98m | #8 |
| 11.0 | "Fake Plastic Snow" | March 9, 2007 | 2.71m | #9 |
| 12.0 | "Sofia's Choice" | March 30, 2007 | 2.36m | #12 |
| 13.0 | "In or Out" | April 6, 2007 | 2.16m | #12 |
| 14.0 | "I'm Coming Out" | April 13, 2007 | 2.48m | #5 |
| 15.0 | "Brothers" | April 20, 2007 | 2.58m | #5 |
| 16.0 | "Derailed" | April 27, 2007 | 2.25m | #15 |
| 17.0 | "Icing on the Cake" | May 4, 2007 | 2.34m | #7 |
| 18.0 | "Don't Ask, Don't Tell" | May 11, 2007 | 2.24m | #13 |
| 19.0 | "Punch Out" | May 18, 2007 | 2.63m | #10 |
| 20.0 | "Petra-Gate" | May 25, 2007 | 2.51m | #6 |
| 21.0 | "Secretaries' Day" | May 25, 2007 | 2.60m | #4 |
| 22.0 | "A Tree Grows in Guadalajara" | June 1, 2007 | 2.59m | #11 |
| 23.0 | "East Side Story" | June 8, 2007 | 3.28m | #9 |
Question:
On what date did the episode "Petra-Gate" air?
Answer:
May 25, 2007