Context and question: Apart from its use as a reactant, H
2 has wide applications in physics and engineering. It is used as a shielding gas in welding methods such as atomic hydrogen welding. H2 is used as the rotor coolant in electrical generators at power stations, because it has the highest thermal conductivity of any gas. Liquid H2 is used in cryogenic research, including superconductivity studies. Because H
2 is lighter than air, having a little more than 114 of the density of air, it was once widely used as a lifting gas in balloons and airships.
What research uses liquid H2?
Answer: cryogenic
Context and question: For centuries, various peoples in modern-day Nigeria traded overland with traders from North Africa. Cities in the area became regional centres in a broad network of trade routes that spanned western, central and northern Africa. In the 16th century, Spanish and Portuguese explorers were the first Europeans to begin significant, direct trade with peoples of modern-day Nigeria, at the port they named Lagos and in Calabar. Europeans traded goods with peoples at the coast; coastal trade with Europeans also marked the beginnings of the Atlantic slave trade. The port of Calabar on the historical Bight of Biafra (now commonly referred to as the Bight of Bonny) become one of the largest slave trading posts in West Africa in the era of the transatlantic slave trade. Other major slaving ports in Nigeria were located in Badagry, Lagos on the Bight of Benin and on Bonny Island on the Bight of Biafra. The majority of those enslaved and taken to these ports were captured in raids and wars. Usually the captives were taken back to the conquerors' territory as forced labour; after time, they were sometimes acculturated and absorbed into the conquerors' society. A number of slave routes were established throughout Nigeria linking the hinterland areas with the major coastal ports. Some of the more prolific slave traders were linked with the Oyo Empire in the southwest, the Aro Confederacy in the southeast and the Sokoto Caliphate in the north.
What is the current name of the Bight of Biafra?
Answer: Bight of Bonny
Context and question: The Legend of Zelda: Twilight Princess is an action-adventure game focused on combat, exploration, and item collection. It uses the basic control scheme introduced in Ocarina of Time, including context-sensitive action buttons and L-targeting (Z-targeting on the Wii), a system that allows the player to keep Link's view focused on an enemy or important object while moving and attacking. Link can walk, run, and attack, and will automatically jump when running off of or reaching for a ledge.[c] Link uses a sword and shield in combat, complemented with secondary weapons and items, including a bow and arrows, a boomerang, bombs, and the Clawshot (similar to the Hookshot introduced earlier in the The Legend of Zelda series).[d] While L-targeting, projectile-based weapons can be fired at a target without the need for manual aiming.[c]
What can be used to shoot without the need to manually target enemies?
Answer:
L-targeting