Problem: Copper has been in use at least 10,000 years, but more than 95% of all copper ever mined and smelted has been extracted since 1900, and more than half was extracted in only the last 24 years. As with many natural resources, the total amount of copper on Earth is vast (around 1014 tons just in the top kilometer of Earth's crust, or about 5 million years' worth at the current rate of extraction). However, only a tiny fraction of these reserves is economically viable, given present-day prices and technologies. Various estimates of existing copper reserves available for mining vary from 25 years to 60 years, depending on core assumptions such as the growth rate. Recycling is a major source of copper in the modern world. Because of these and other factors, the future of copper production and supply is the subject of much debate, including the concept of peak copper, analogous to peak oil.
How much of mined cooper has been extracted in the last 24 years?
The answer is the following: more than half

Problem: Bohr also introduced the quantity , now known as the reduced Planck constant, as the quantum of angular momentum. At first, Bohr thought that this was the angular momentum of each electron in an atom: this proved incorrect and, despite developments by Sommerfeld and others, an accurate description of the electron angular momentum proved beyond the Bohr model. The correct quantization rules for electrons in which the energy reduces to the Bohr model equation in the case of the hydrogen atom were given by Heisenberg's matrix mechanics in 1925 and the Schrodinger wave equation in 1926: the reduced Planck constant remains the fundamental quantum of angular momentum. In modern terms, if J is the total angular momentum of a system with rotational invariance, and Jz the angular momentum measured along any given direction, these quantities can only take on the values
What scientist used matrix mechanics to bring electron behavior in line with the Bohr model?
The answer is the following: Heisenberg

Problem: In 1063, Ferdinand I of Castile divided his realm among his sons, and the Kingdom of Galicia was granted to Garcia II of Galicia. In 1072, it was forcibly annexed by Garcia's brother Alfonso VI of Leon; from that time Galicia was united with the Kingdom of Leon under the same monarchs. In the 13th century Alfonso X of Castile standardized the Castilian language and made it the language of court and government. Nevertheless, in his Kingdom of Galicia the Galician language was the only language spoken, and the most used in government and legal uses, as well as in literature.
Who was it that in 1063 gave rule over Galicia to his son?
The answer is the following: Ferdinand I

Problem: During the Consulate, Napoleon faced several royalist and Jacobin assassination plots, including the Conspiration des poignards (Dagger plot) in October 1800 and the Plot of the Rue Saint-Nicaise (also known as the Infernal Machine) two months later. In January 1804, his police uncovered an assassination plot against him that involved Moreau and which was ostensibly sponsored by the Bourbon family, the former rulers of France. On the advice of Talleyrand, Napoleon ordered the kidnapping of the Duke of Enghien, violating the sovereignty of Baden. The Duke was quickly executed after a secret military trial, even though he had not been involved in the plot. Enghien's execution infuriated royal courts throughout Europe, become one of the contributing political factors for the outbreak of the Napoleonic Wars.
What was another name for the Conspiration des poignards?
The answer is the following:
Dagger plot