The 1920s were both a "roaring" and a turbulent decade for the United States. A thriving interest in all things modern--technology, jazz, social mores--clashed with a cultural backlash against growing multiculturalism and changing values.
A time of affluence. A time of fear. During Eisenhower's eight years in office, the United States fought a war in Korea, fretted about communism in Hollywood, and began a space program.
The 1960s might be the most tumultuous decade in American history, when simmering resentments boiled over into rage against the status quo. From the assassination of John F. Kennedy to the My Lai Massacre, after the bloody Sixties the United States would never be the same.
Stagflation, Watergate, the Iran Hostage Crisis -- the 1970s were tough years for the United States.
The presidency of Ronald Reagan issued in a more conservative era in the United States.
Learn about the presidency of Bill Clinton and the acceleration of globalization.
In this program, we'll look at the production of Green Fluorescent Protein. GFP is used as a biological marker, and when attached to a drug it can provide researchers with a visual story of where the drug goes. It's a fluorescent dye that's very well tolerated by most cells and doesn't interfere with normal cellular function. Let's examine the 3 main phases of GFP production – Fermentation, Recovery, and Purification. Fermentation is basically cell farming. We program cells to produce a product, we nurture them as they grow and reproduce, and then we harvest them. In recovery we separate our product from the cells where they were housed. And then in purification we go a step further by removing everything else that's contaminating our product leaving us with a very pure, concentrated solution.
The video resource "2,000 Years of Chinese History! The Mandate of Heaven and Confucius: World History #7" is included in the "World History" course from the resources series of "Crash Course". Crash Course is a educational video series from John and Hank Green.
The video resource "2001 - A Space Odyssey: Crash Course Film Criticism #15" is included in the "Film Criticism" course from the resources series of "Crash Course". Crash Course is a educational video series from John and Hank Green.
2003 AIME II Problem 1
perfect squares integers square root
A little trigonometry to figure out the area of a triangle
Minimum members in a committee
Probability of moving to a vertex
Trigonometry and geometry to find the area of an equilateral (but not regular) hexagon
2003 AIME II Problem 3
Volume of a wedge cut from a cylindrical log
2003 AIME II Problem 5 Minor Correction
This video is from the Khan Academy subject of Math on the topic of Mathlete training and it covers 2003 AIME II Problem 6.
This video is from the Khan Academy subject of Math on the topic of Geometry and it covers 2003 AIME II Problem 7.