What are two sources of water for the future?

Which phrase describes the time it takes for a planet to make a complete rotation

Select the natural regions. delta denver forest georgia north america plateau stream

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