In the word "hastation", stress falls on:

HAS-TA-TION

The stress falls on the TA syllable.

Explanation:

Proper communication involves ensuring that words are pronounced corrected with the stress situated on the right syllable. That is putting greater emphasis on the right syllable especially when the word is multisyllabic.

A syllable is the various parts into which the vowel sounds which make of a word may be divided. For example:

DI-VI-DED

EX-AM-PLE

COM-MU-NI-CA-TION

You'd notice that the stress falls on the underlined words. Imagine trying to put that stress on any other syllable?

You'd notice that it sounds weird or out of place. This is the reason why it is critical to place the stress correctly.

Cheers