Q: Superconductors are materials with a resistivity of? Read this paragraph and choose the correct option from the provided answers: 34.6 High-temperature Superconductors Superconductors are materials with a resistivity of zero. They are familiar to the general public because of their practical applications and have been mentioned at a number of points in the text. Because the resistance of a piece of superconductor is zero, there are no heat losses for currents through them; they are used in magnets needing high currents, such as in MRI machines, and could cut energy losses in power transmission. But most superconductors must be cooled to temperatures only a few kelvin above absolute zero, a costly procedure limiting their practical applications. In the past decade, tremendous advances have been made in producing materials that become superconductors at relatively high temperatures. There is hope that room temperature superconductors may someday be manufactured. Choices: - above zero - greater density - high magnitude - zero A:
zero

Q: What describes how close an estimate is to a known standard? Read this paragraph and choose the correct option from the provided answers: Accuracy describes how close an estimate is to a known standard. Choices: - diversity - frequency - precision - accuracy A:
accuracy

Q: Q: Which type of weathering causes changes int he rocks materials, chemical or mechanical? Read this paragraph and choose the correct option from the provided answers: The original rock is the source of the inorganic portion of the soil. Mechanical weathering breaks rock into smaller pieces. Chemical reactions change the rock's minerals. Choices: - liquid - nuclear - mineral - chemical A:
A: chemical

Question: Q: Different feeding "positions" in a food chain or web are associated with what kinds of levels? Read this paragraph and choose the correct option from the provided answers: The different feeding positions in a food chain or web are called trophic levels. Choices: - benthic - autotrophic - heptic - trophic A:
Answer: trophic

*Question*
Q: What are biological catalysts that speeds up biochemical reactions? Read this paragraph and choose the correct option from the provided answers: This super fast train can obviously reach great speeds. And there's a lot of technology that helps this train go fast. Speaking of helping things go fast brings us to enzymes. Life could not exist without enzymes. Essentially, enzymes are biological catalysts that speed up biochemical reactions. Choices: - carbohydrates - hormones - proteins - enzymes A:
**Answer**
enzymes

Q: Q: Friction causes the molecules on rubbing surfaces to move faster, which produces what? Read this paragraph and choose the correct option from the provided answers: You know that friction produces heat. That's why rubbing your hands together makes them warmer. But do you know why the rubbing produces heat? Friction causes the molecules on rubbing surfaces to move faster, so they have more heat energy. Heat from friction can be useful. It not only warms your hands. It also lets you light a match (see Figure below ). On the other hand, heat from friction can be a problem inside a car engine. It can cause the car to overheat. To reduce friction, oil is added to the engine. Oil coats the surfaces of moving parts and makes them slippery so there is less friction. Choices: - life - precipitation - cold - heat A:
A: heat