This 10-minute video lesson covers the structure of the Earth: The crust, mantle, and core. [Cosmology and Astronomy playlist: Lesson 44 of 85]

This 9-minute video lesson looks at supermassive black holes. [Cosmology and Astronomy playlist: Lesson 34 of 85]

This 2-minute video lesson provides a clarification about supernovae. [Cosmology and Astronomy playlist: Lesson 29 of 85]

This 12-minute video lesson looks at supernovae. [Cosmology and Astronomy playlist: Lesson 28 of 85]

This 6-minute video lesson looks at the Mohorovicic Seismic Discontinuity: the boundary between crust and mantle (or Moho). [Cosmology and Astronomy playlist: Lesson 54 of 85]

This 10-minute video lesson discusses the differences between BC, BCE, AD and CE. It includes a little bit about the birth of Jesus as well. [Cosmology and Astronomy playlist: Lesson 65 of 85]

This 2-minute video lesson looks at the causes precession and other orbital changes. [Cosmology and Astronomy playlist: Lesson 74 of 85]

This 13-minute video lesson looks at the process of stars becoming white and black dwarfs. [Cosmology and Astronomy playlist: Lesson 18 of 85]

This 7-minute video lesson explains why cepheids pulsate. [Cosmology and Astronomy playlist: Lesson 32 of 85]

This 8-minute video lesson looks at why gravity gets so strong near dense objects. [Cosmology and Astronomy playlist: Lesson 33 of 85]

This 4-minute video lesson explains why S-Waves only travel in solids. [Cosmology and Astronomy playlist: Lesson 52 of 85]

This art history video discussion examines Gustave Courbet's "The Artist's Studio; A real allegory summing up seven years of my artistic and moral life", oil on canvas, 1854-55 (Musee d'Orsay, Paris).

This art history video discussion looks at Thomas Couture's "Romans of the Decadence," 1847, oil on canvas. (Musج©e d‰غھOrsay, Paris).

This art history video discussion examines Lucus Cranach the Elder's "Adam and Eve", 1526, oil on panel (Courtauld Gallery, London).

This video illustrates how a change in the price of one good affects the quantity demanded of another good (complement or substitute).

Discussion of inflation, the CPI index and owners' equivalent rent. [Economics playlist: Lesson 8 of 20]

Discussion of impact of China buying U.S. Bonds. [Economics playlist: Lesson 13 of 20]

Discussion of China Pegs to Dollar to keep trade imblance. [Economics playlist: Lesson 12 of 20]

Data on Chinese foreign assets increase in 2010. [Economics playlist: Lesson 16 of 20]