Problem: I know that the answer to the question "Which is smaller, human eyes or photons?" is in "Equivalently, the smallness of the Planck constant reflects the fact that everyday objects and systems are made of a large number of particles. For example, green light with a wavelength of 555 nanometres (the approximate wavelength to which human eyes are most sensitive) has a frequency of 7014540000000000000♠️540 THz (7014540000000000000♠️5401012 Hz). Each photon has an energy E = hf = 6981358000000000000♠️3.581019 J. That is a very small amount of energy in terms of everyday experience, but everyday experience is not concerned with individual photons any more than with individual atoms or molecules. An amount of light compatible with everyday experience is the energy of one mole of photons; its energy can be computed by multiplying the photon energy by the Avogadro constant, NA 7023602200000000000♠️6.0221023 mol1. The result is that green light of wavelength 555 nm has an energy of 7005216000000000000♠️216 kJ/mol, a typical energy of everyday life.". Can you tell me what it is?

A: photons

Problem: I know that the answer to the question "what is been discussed?" is in "A wide range of beliefs and practices is found across the world among those who call themselves Christian. Denominations and sects disagree on a common definition of "Christianity". For example, Timothy Beal notes the disparity of beliefs among those who identify as Christians in the United States as follows:". Can you tell me what it is?

A: Christianity

Problem: I know that the answer to the question "What was there demand for by people who bought the Macintosh II?" is in "Updated Motorola CPUs made a faster machine possible, and in 1987 Apple took advantage of the new Motorola technology and introduced the Macintosh II at $5500, powered by a 16 MHz Motorola 68020 processor. The primary improvement in the Macintosh II was Color QuickDraw in ROM, a color version of the graphics language which was the heart of the machine. Among the many innovations in Color QuickDraw were the ability to handle any display size, any color depth, and multiple monitors. The Macintosh II marked the start of a new direction for the Macintosh, as now for the first time it had an open architecture with several NuBus expansion slots, support for color graphics and external monitors, and a modular design similar to that of the IBM PC. It had an internal hard drive and a power supply with a fan, which was initially fairly loud. One third-party developer sold a device to regulate fan speed based on a heat sensor, but it voided the warranty. Later Macintosh computers had quieter power supplies and hard drives.". Can you tell me what it is?

A: a device to regulate fan speed based on a heat sensor

Problem: I know that the answer to the question "What subject is concerned with economic trends?" is in "Nutritional anthropology is a synthetic concept that deals with the interplay between economic systems, nutritional status and food security, and how changes in the former affect the latter. If economic and environmental changes in a community affect access to food, food security, and dietary health, then this interplay between culture and biology is in turn connected to broader historical and economic trends associated with globalization. Nutritional status affects overall health status, work performance potential, and the overall potential for economic development (either in terms of human development or traditional western models) for any given group of people.". Can you tell me what it is?

A:
biology