Water that flows downhill along earth's surface is called
a. rain.
b. beach hydraulics.
c. runoff.
d. cycles.

Geologists know that potassium-40 decays to argon-40, with a half-life of 1.3 billion years. if an analysis of a feldspar crystal in a sample of granite shows that 75 percent of the potassium-40 atoms have decayed to form argon-40, what is the age of the granite

Rah is completing a school project on the expansion of fast food restaurants across the united states. she finds a map that shows a clear pattern of restaurants beginning in the east and expanding west. this map was most likely created using the technology of

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