Here's why:
* Schwa sound: The schwa sound is a very short, unstressed vowel sound, represented by the symbol /ə/. It's like the "uh" sound in words like "about" or "sofa".
* "Notify" pronunciation: The word "notify" has the stress on the second syllable, "ti". This means the first syllable "no" is unstressed.
* Unstressed vowels: Unstressed vowels in English often reduce to the schwa sound.
Therefore, the schwa sound in "notify" is the "uh" sound in the first syllable "no".