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[Volcanic Hazards] Which of the following substances has higher viscosity?

[Oceans] So, sea level is rising…What does that mean for our future? From computer models, scientists have produced the following graph to help us visualize expected amounts of sea-level change. Based on the graph, categorize the following estimations as to whether they are too high, too low, or within predicted rates of sea-level rise.

[Oceans] Now let’s put this formula to use. To understand the more recent trend of sea-level rise, we have to look on the scale of decades instead of hundreds of millions of years. The following graph shows the change in sea level from 1880 to 2010. What is the approximate rate of sea-level rise during this period? What is the approximate rate of sea-level rise during this period? Remember, rate is calculated as change divided by time.

[Winds, Fronts, and Cyclones] Warm air rises above cold air at a front. This is because warm air is less dense than cold air. Along a warm front, warm air advances over a retreating cold air mass. Select the image below that represents a warm front.

[Volcanic Hazards] Based on what you know about viscosity and composition, rank the magma compositions from least explosive to most explosive. Hint: Explosivity occurs when gases are unable to escape from a thick magma, causing pressure to build up.

[Volcanic Hazards] Temperature influences the viscosity of many materials. Would you expect a high-temperature magma to be more or less viscous than a lower temperature magma?  

[Volcanic Hazards] Match each term below to the appropriate image.

 [Minerals] Cleavage and hardness are two separate characteristics of a mineral. Take diamonds, for example. The tag line is that “diamonds are forever.” This is true if you think only about scratching. Diamonds are very scratch-resistant, so they have a high hardness rating on Mohs scale for hardness. If you take a hammer to a diamond, you will see that it fractures as easily as many other minerals. Odds are you will upset someone as well. Below are two minerals. Use Mohs scale for hardness to determine which mineral is harder. Click on the harder mineral.

[From Big Bang to Blue Marble] A geologist discovers a solid material with an unordered atomic arrangement that formed from rapid cooling of molten rock. Which material classification is most accurate?

[Plate Tectonics] On the following map, there are six boxes at different plate boundaries. Using the arrows showing relative plate motion, label each box as a convergent or divergent plate boundary.