Problem: Another potential weapon system for anti-aircraft use is the laser. Although air planners have imagined lasers in combat since the late 1960s, only the most modern laser systems are currently reaching what could be considered "experimental usefulness". In particular the Tactical High Energy Laser can be used in the anti-aircraft and anti-missile role. If current developments continue, some[who?] believe it is reasonable to suggest that lasers will play a major role in air defence starting in the next ten years.
The use of lasers in anti-aircraft warfare is currently considered what?
The answer is the following: experimental usefulness

Problem: Serological methods are highly sensitive, specific and often extremely rapid tests used to identify microorganisms. These tests are based upon the ability of an antibody to bind specifically to an antigen. The antigen, usually a protein or carbohydrate made by an infectious agent, is bound by the antibody. This binding then sets off a chain of events that can be visibly obvious in various ways, dependent upon the test. For example, "Strep throat" is often diagnosed within minutes, and is based on the appearance of antigens made by the causative agent, S. pyogenes, that is retrieved from a patients throat with a cotton swab. Serological tests, if available, are usually the preferred route of identification, however the tests are costly to develop and the reagents used in the test often require refrigeration. Some serological methods are extremely costly, although when commonly used, such as with the "strep test", they can be inexpensive.
What is the antigen bound to by the antibody usually?
The answer is the following: a protein or carbohydrate made by an infectious agent

Problem: In the colonial years, while conditions were more fluid, white women, indentured servant or free, and African men, servant, slave or free, made unions. Because the women were free, their mixed-race children were born free; they and their descendants formed most of the families of free people of color during the colonial period in Virginia. The scholar Paul Heinegg found that eighty percent of the free people of color in North Carolina in censuses from 1790–1810 could be traced to families free in Virginia in colonial years.
What is Paul Heinegg?
The answer is the following: scholar

Problem: Any living organism relies on an external source of energy—radiation from the Sun in the case of green plants, chemical energy in some form in the case of animals—to be able to grow and reproduce. The daily 1500–2000 Calories (6–8 MJ) recommended for a human adult are taken as a combination of oxygen and food molecules, the latter mostly carbohydrates and fats, of which glucose (C6H12O6) and stearin (C57H110O6) are convenient examples. The food molecules are oxidised to carbon dioxide and water in the mitochondria
How many daily calories are recommended for a human adult?
The answer is the following:
1500–2000