Answer:
The United States of America is a North American nation that is the world's most dominant economic and military power. Likewise, its cultural imprint spans the world, led in large part by its popular culture expressed in music, movies and television.
A simile can be found when using "like" or "as" between two things. Example: I'm as happy as a clown.
Your question would be a metaphor. Both things are being compared to a science expieriment, probably meaning that they need to have an outcome, but it isn't known for sure if it will be a good or bad outcome.
Things like this can be taken many ways, so if you think something else, I'm sure it would work as well.
Dr. Elizabeth Blackwell was the first woman to receive a medical degree. She opened doors for womens education in medicine.
The list you look for is a). The verb 'to go' is an irregular verb because it completely changes its form in the past: went - gone.
