nasalizations

i noticed that in the first interactive audio lesson (introduction), the "hain" in the phrase "aap kaisee hain" is nasalized. however, in the first language and culture lesson (greetings), the same phrase uses the non-nasalized "hai" instead. this difference is also reflected in the hindi script. what's up with that? are the two interchangeable or is there a mistake in the spelling? help!

you are correct, it should be hain, because aap is plural

namaste mujhe points deejiye mujhe greedy log hu