大有作为

This series also covers the essential concepts of astronomy: gravity, the light spectrum, Earth's magnetic field, the solar system, the sun, Kepler's...

Every year, millions of high school and college students walk into their first geometry class thinking: "Circles and squares. How tough can it be?"...

Physics is a system of models of nature according to which all phenomena are explained in terms of matter and force. Sound confusing? It doesn't have...

Morgan Spurlock tours the Middle East to discuss the war on terror with Arabic people.

Procreation is the social duty of all fertile women, was the political thinking during the 1960s and 1970s in Romania. In 1966, Ceaucescu issued...

Taking stock of the extraordinary adventure of "Pif Gadget", a French publishing phenomenon of the 1970s-80s and even of the whole history of...

The dangers of LSD are driven home to teenagers in this classroom training film, which is "narrated" by an LSD tab. The "tab" tells kids that he is...

Discover the unsettling truths behind the world's most pivotal events in "The IMPACT." This powerful documentary dives deep into the shadows of...

A portrait of Chinese writer Liu Xiaobo (1955-2017), a witness of the Tiananmen Square massacre (1989), a dissident, a woodpecker who tirelessly...

EVERYTHING YOU NEED TO KNOW TO ACE PRE-CALCULUS IS AT YOUR FINGERTIPS: functions, polynomials, f(x), RATIONAL FUNCTIONS, standard form for rational...