The observational fact about a cepheid variable star that leads to a measurement of its distance from earth is that its period of variation is directly related to its

What causes different seasons on Earth? A. The way heat energy reflects off of Earth because of the angle at which it hits B. The way that Earth gets closer and farther from the sun throughout the year C. The fact that Earth goes along an ecliptic D.

Describe why world human population growth is of such concern

How does the heartland theory differ from the rimland theory? The heartland theory was developed in the 1800s, while the rimland theory is a modern concept.

Europe and asia are divided by

Does the El Nino make usually wet areas dry?

Where do the lines of latitude meet?

How far is geographic second? A. Around 100 feet B. Around 1,000 feet C. 5,000 feet D. None of the above

How do we know about the history of the Māori? A. There is no history of the Māori. B. Oral stories passed from generation to generation C. Stone carvings D. Well preserved written history

What are some ways in which Islam was spread?

Explain why there is global warming.