The gap in the ozone layer over the North Pole can expand each summer enough that it exposes regions as far south as Sweden by heightened UV radiation, also increasing rates of skin cancer in the northern regions by as much as 50 percent.

This quiz set has 75+ questions.

It is very, very challenging to score highly on the Verbal section. Scores above 44 are rare; anywhere in the 45 to 51 range puts you in the top 1% of test-takers.