Astronomers have found new evidence that the number of galaxies in the universe is not 10 billion, as previously beli...

Meredith on November 10, 2019

Why A

I'm confused as to why A is correct ... even if it is a small percentage the addition of 40 million would still have impact.

1 Reply

on November 11, 2019

Hello @Meredith,

You are correct that the addition of 40 billion galaxies would have an impact. However, the word "tiny" tells us that this impact would be very small. If galaxies as a whole are a tiny percentage of the universe's total mass, then multiplying this percentage by 5 is not going to have a significant impact on total mass. A key phrase here is "virtually unchanged." If the stimulus had simply said "unchanged," then I would agree with you. However, virtually leaves room for slight differences.