1.Before she followed the white rabbit through the tiny door, Alice has (shrank, shrunk) to a very small size!

2.Vulcan's hammer (rang, rung) as he worked metal for the Roman gods.
3.Not only have I never (rode, ridden) a roller coaster, but I probably never will.

1.shrunk
2.rang
3.ridden

Great! All are correct!

To determine the correct verb forms in the given sentences, we need to understand the past participle forms of the verbs "shrink," "ring," and "ride."

1. Before she followed the white rabbit through the tiny door, Alice has (shrank, shrunk) to a very small size!
To find the correct form, we can use the rule that "shrink" is an irregular verb. The past tense form of "shrink" is "shrank," but the past participle form is "shrunk." In this sentence, we need to use the past participle form to match the present perfect tense "has," so the correct answer is "shrunk."

2. Vulcan's hammer (rang, rung) as he worked metal for the Roman gods.
For the verb "ring," we can use the rule that it is a regular verb. The simple past tense form is "rang," and the past participle form is "rung." Since this sentence is in the simple past tense, the correct answer is "rang."

3. Not only have I never (rode, ridden) a roller coaster, but I probably never will.
For the verb "ride," we can use the same rule as in sentence 1. The past tense form of "ride" is "rode," but the past participle form is "ridden." In this sentence, we need to use the past participle form to match the present perfect tense "have," so the correct answer is "ridden."

So the correct forms are:
1. shrunk
2. rang
3. ridden