Answer the following question given this paragraph: Figure below shows a diagram of Mercury's interior. Mercury is one of the densest planets. Scientists think that the interior contains a large core made mostly of melted iron. Mercury's core takes up about 42% of the planet's volume. Mercury's highly cratered surface is evidence that Mercury is not geologically active. Q: What do scientist's believe mercury's core is mostly made of? Choices: - water - quicksilver - helium gas - melted iron A:
melted iron
Answer the following question given this paragraph: The speed of sound is the distance that sound waves travel in a given amount of time. The speed of sound in dry air at 20 C is 343 meters per second. Q: What is the distance that sound waves travel in a given amount of time called? Choices: - velocity of sound - momentum of sound - force of sound - speed of sound A:
speed of sound
Q: Answer the following question given this paragraph: Amphibians are vertebrates that live part of the time in fresh water and part of the time on land. They were the first vertebrates to evolve four legs and colonize the land. They most likely evolved from lobe-finned fish. Modern amphibians include frogs, toads, salamanders, newts, and caecilians. They are ectotherms, so they have little control over their body temperature. This allows them to be active in warm weather, but they become sluggish when the temperature cools. Q: Frogs are amphibians that live part of the time in fresh water and rest of the time where? Choices: - underground - in stagnant water - in salt water - on land A:
A: on land
Question: Answer the following question given this paragraph: Stress is the force applied to an object. Stresses can be confining, compression, tension, or shear. Q: The force applied to an object is called? Choices: - gravity - torque - strain - stress A:
Answer: stress
*Question*
Answer the following question given this paragraph: Magnesium (Mg) and calcium (Ca) are also important macronutrients. The role of calcium is twofold: to regulate nutrient transport, and to support many enzyme functions. Magnesium is important to the photosynthetic process. These minerals, along with the micronutrients, which are described below, also contribute to the plant's ionic balance. In addition to macronutrients, organisms require various elements in small amounts. These micronutrients, or trace elements, are present in very small quantities. They include boron (B), chlorine (Cl), manganese (Mn), iron (Fe), zinc (Zn), copper (Cu), molybdenum (Mo), nickel (Ni), silicon (Si), and sodium (Na). Deficiencies in any of these nutrientsparticularly the macronutrientscan adversely affect plant growth (Figure 31.4. Depending on the specific nutrient, a lack can cause stunted growth, slow growth, or chlorosis (yellowing of the leaves). Extreme deficiencies may result in leaves showing signs of cell death. Q: What process is magnesium important to? Choices: - dna replication - carbon cycle - absorption - photosynthetic A:
**Answer**
photosynthetic
(Q).
Answer the following question given this paragraph: Detecting Electromagnetic Waves from Space A final note on star gazing. The entire electromagnetic spectrum is used by researchers for investigating stars, space, and time. As noted earlier, Penzias and Wilson detected microwaves to identify the background radiation originating from the Big Bang. Radio telescopes such as the Arecibo Radio Telescope in Puerto Rico and Parkes Observatory in Australia were designed to detect radio waves. Infrared telescopes need to have their detectors cooled by liquid nitrogen to be able to gather useful signals. Since infrared radiation is predominantly from thermal agitation, if the detectors were not cooled, the vibrations of the molecules in the antenna would be stronger than the signal being collected. The most famous of these infrared sensitive telescopes is the James Clerk Maxwell Telescope in Hawaii. The earliest telescopes, developed in the seventeenth century, were optical telescopes, collecting visible light. Telescopes in the ultraviolet, X-ray, and -ray regions are placed outside the atmosphere on satellites orbiting the Earth. The Hubble Space Telescope (launched in 1990) gathers ultraviolet radiation as well as visible light. In the X-ray region, there is the Chandra X-ray Observatory (launched in 1999), and in the -ray region, there is the new Fermi Gamma-ray Space Telescope (launched in 2008taking the place of the Compton Gamma Ray Observatory, 19912000. PhET Explorations: Color Vision Make a whole rainbow by mixing red, green, and blue light. Change the wavelength of a monochromatic beam or filter white light. View the light as a solid beam, or see the individual photons. Q: What is used for cooling detectors of infrared telescopes? Choices: - hand nitrogen - material nitrogen - carbon dioxide - liquid nitrogen A:
(A).
liquid nitrogen