Answer the following question given this paragraph: The water cycle plays an important role in weather. When liquid water evaporates, it causes humidity. When water vapor condenses, it forms clouds and precipitation. Humidity, clouds, and precipitation are all important weather factors. Q: What happens when liquid water evaporates? Choices: - condensation - seawater happens - snow - humidity happens A:
humidity happens
Answer the following question given this paragraph: The fetus is connected to the placenta through the umbilical cord. This is a long tube that contains two arteries and a vein. Blood from the fetus enters the placenta through the umbilical arteries. It exchanges gases and other substances with the mother's blood. Then it travels back to the fetus through the umbilical vein. Q: The umbilical cord connects the fetus to what structure? Choices: - Ovaries - uterus - cell - placenta A:
placenta
Q: Answer the following question given this paragraph: Q: By impacting plant species and the animals they support, destruction of habitat threatens what event? Choices: - overpopulation - depletion - mutation - extinction A:
A: extinction
Question: Answer the following question given this paragraph: Like a chemical compound, a mixture consists of more than one chemical substance. Unlike a compound, a mixture does not have a fixed chemical composition. The substances in a mixture can be combined in any proportions. A mixture also does not involve a chemical reaction. Therefore, the substances in a mixture are not changed into unique new substances, and they can be separated from each other without a chemical reaction. Q: What is the term for a combination of substances in which there is no chemical reaction? Choices: - a combination - a solute - a solution - a mixture A:
Answer: a mixture
*Question*
Answer the following question given this paragraph: The electrons in an atom tend to be arranged in such a way that the energy of the atom is as low as possible. The ground state of an atom is the lowest energy state of the atom. When those atoms are given energy, the electrons absorb the energy and move to a higher energy level. These energy levels of the electrons in atoms are quantized, meaning again that the electron must move from one energy level to another in discrete steps rather than continuously. An excited state of an atom is a state where its potential energy is higher than the ground state. An atom in the excited state is not stable. When it returns back to the ground state, it releases the energy that it had previously gained in the form of electromagnetic radiation. Q: What is the lowest energy state of the atom called? Choices: - work state - active state - base state - ground state A:
**Answer**
ground state
Q: Answer the following question given this paragraph: pressure above the liquid. Molecules in the gas phase can collide with the liquid surface and reenter the liquid via condensation. Eventually, a steady state is reached in which the number of molecules evaporating and condensing per unit time is the same, and the system is in a state of dynamic equilibrium. Under these conditions, a liquid exhibits a characteristic equilibrium vapor pressure that depends only on the temperature. We can express the nonlinear relationship between vapor pressure and temperature as a linear relationship using the ClausiusClapeyron equation. This equation can be used to calculate the enthalpy of vaporization of a liquid from its measured vapor pressure at two or more temperatures. Volatile liquids are liquids with high vapor pressures, which tend to evaporate readily from an open container; nonvolatile liquids have low vapor pressures. When the vapor pressure equals the external pressure, bubbles of vapor form within the liquid, and it boils. The temperature at which a substance boils at a pressure of 1 atm is its normal boiling point. Q: Molecules in the gas phase can collide with the liquid surface and reenter the liquid via what? Choices: - fermentation - combustion - liquidation - condensation A:
A: condensation