Here's why:
* "Me" is the correct pronoun in this case. It's the object of the preposition "to." The sentence is essentially saying "Please respond to Mike and respond to me."
* "You" would be incorrect because it's not the intended recipient of the response. The instruction is to respond to Mike and the speaker.
Here are some other options, depending on the context:
* "Please respond back to Mike and I." This is grammatically correct but sounds slightly formal.
* "Please respond to Mike and me." This is the most common and natural-sounding option.
* "Please reply to Mike and me." This is a good alternative to "respond back."