If the age of the most layer of a rock sample is more than 2 million years, which of the following could be the age of the upper layers. A) Less than 1 million B) Greater than 3.5 million C) Between 2 million and 3 million
D) Between 3 million and 3.5 million

Why is the huronian supergroup rock formation particularly interesting to scientists? because it looks like a cross-section of a giant, stone encyclopedia because it formed during the period when oxygen began to accumulate in the atmosphere because it contains unusually large amounts of oxygen and sulfur because it dramatically altered the planet's development when it first formed