"the seasoned equestrian vaulters were determined to win it." in your own words, identify the case of the underlined pronoun (it) as well as the antecedent to which it refers. if the reference is ambiguous or indefinite, rewrite the sentence to correct the error.

Based on the given sentence above, the pronoun used is the word "it", and the case of this pronoun is nominative case. In the sentence, the antecedent that is referring to is ambiguous or vague, meaning, there is no clear noun that this pronoun is identifying to. The subject "vaulters" is also not antecedent since it is referring to something that the vaulters are trying to win. Hope this answer helps.