Why even though we traveled
in a straight line east toward the Sun, our altitude
was increasing in the first several steps.

The point where two air masses meet is called a

Plants can have a positive and negative effect on the rate of weathering

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