What type of environments did hunter-gatherers live in? A. all types of environments
B. only in the flat grasslands
C. only in the warm desert
D. only in the lush forests

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