B I s the right answer good luck
Why might a post classical civilization want to conquer Egypt and the Nile River Valley? It's fertile land provided the foundation for the first human civilizations and its access to the Persian Gulf and location between Europe, Asia, and Africa made it a center of trade.
1. Tiltmeter matches with <span>"The _____ suggests that the ground has risen about 2 inches."
2. </span><span>Richter scale: </span>"People in the cafeteria felt the quake, but those in the conference room didn't. The earthquake magnitude must've been around 3 on the _____."
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3. </span>Mercalli intensity scale: <span>"If you want to measure the earthquake based on the level of damage incurred, use the _____."
4. S</span>eismograph: <span>"The _____ records P waves first, then S waves."
5. C</span>orrelation Spectrometer (COSPEC): "Look! That volcano is emitting smoke! Grab your _____ and measure the sulfur dioxide content."
6. Moment Magnitude Scale: <span>"I would use a _____ to measure the magnitude of earthquakes that occur over large areas." </span>
Until the early Proterozic there were only negligible amounts of free oxygen in the atmosphere
