Study the major rivers on the map of the United States. A map of the U S with rivers shown. Parts of the map are labeled A, B, C, and D. A is near Washington and Oregon. B is near New Mexico and Colorado. C is near South Dakota and Iowa. D is near Arkansas and Mississippi. Which river is marked with the letter B?

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