*Question*
Read the passage below and choose the right answer to the following question (choices are Surface or Mountain Peak ): The surface is heated by the Sun and some of that heat radiates back into the air. This makes the temperature higher near the surface than at higher altitudes. Paul started at the base of a mountain and climbed to its peak. The sky was clear and the sun was beating down on him all day. However, he noticed there was a clear temperature difference between the surface's temperature and the temperature at the top of the mountain peak. Where would he feel more heat Surface or Mountain Peak?
**Answer**
Surface

*Question*
Read the passage below and choose the right answer to the following question (choices are United States or China ): Because richer nations use more fossil fuels, they also cause more air pollution and global warming than poorer nations do. Chris is studying two countries. He finds that China has half as many factories putting out fossil fuels into the air than the United States. Based on this information, the factories in United States or China are causing more air pollution?
**Answer**
United States

*Question*
Read the passage below and choose the right answer to the following question (choices are frequency or amplitude ): The closer together the particles are, the greater the amplitude of the wave. When crests get higher in a wave what increases frequency or amplitude?
**Answer**
frequency

*Question*
Read the passage below and choose the right answer to the following question (choices are increases or decreases ): The more acidic a solution is, the closer its pH value will be to 0 If Mona is making lemonade and she increases the acidity of it by adding more lemons, what happens to its closeness to pH 0 increases or decreases?
**Answer**
increases