[Stellar Evolution] Whereas spectral classes describe a star’s surface temperature, the absolute magnitude of a star describes the star’s true brightness, or luminosity. The image below shows the same 60-watt lightbulb at various distances from the viewer. Which of the following statements accurately describes the magnitude of the lightbulbs as shown?

[Tornadoes, Thunderstorms & Hurricanes] Buoyant air updrafts often lead to thunderstorm development. Place the following images in the correct order below to show the life cycle of a thunderstorm.      

[Climate Change] Another anthropogenic change the Earth experiences is pollution. Match the type of pollution with the anthropogenic cause.  

[Stellar Evolution] Stars that are more massive than our Sun will undergo a different life cycle. In the following animation, click on the “Topics” menu and select “Massive Stars.” Watch the animation, and then complete the problem that follows. Click here to open the animation in a new window. Place the following events of a massive star’s life cycle in chronological order.  

[Planetary Geology] Differentiation led to the Earth separating into layers based on density. Drag the layer labels to the correct locations on the triangular schematic of Earth’s interior below.

[Planetary Geology] When thinking about the cosmos, it is easy to be overwhelmed by its immense scale. Let’s start by putting everything into context according to scale. Order the following terms, starting with the largest and progressing to the smallest.

[Climate Change] Let’s look at the CO2 record from a bit further back in time to provide more context. We can see that there are natural cycles in CO2 on a ~100,000 year cycle. These coincide with the glacial/interglacial cycle. On the image, select the parts of the historical record where you would expect glaciations to occur.

[Planetary Geology] Matter within the Universe exists primarily in solid, liquid, or gas states. These states have different characteristics. Drag each characteristic to the picture of the phase that it best describes.

​The rules of evidence are important not only to safeguard the rights of accused persons in a fair trial but also to ensure _____.

The dying declarations exception to the hearsay rule has been justified on the basis of public necessity. statements against penal interest.​