Query Letter to Imprints of Same Publisher

Greetings. Jeremy Tarcher Inc. and Perigee Books are both imprints of Penguin Publishing, but Tarcher and Perigee are listed as separate publishers in the 2007 Writer's Market Deluxe Edition. I would like to send a query letter to both of them. Both focus on my genre, and both share my vision on book projects, but they have different standards and guidelines. They appear to be different publishers. Does anyone know if it would be like submitting to the same exact publisher, or are they two entirely separate entities from Penguin?

Thanks for any help you can provide.

Thank you all very much for the replies. Thank you Cath for moving the thread to the proper place, and thanks for the welcome.

Good wishes to all.