*Question*
Q: What part of an experiment or other investigation consists of the individuals or events that are studied? Read this paragraph and choose the correct option from the provided answers: The sample in an experiment or other investigation consists of the individuals or events that are studied. Typically, the sample is much smaller than all such individuals or events that exist in the world. Whether the results based on the sample are true in general cannot be known for certain. However, the larger the sample is, the more likely it is that the results are generally true. Similarly, the more times that an experiment is repeated and the same results obtained, the more likely the results are valid. This is why scientific experiments should always be repeated. Choices: - hypothesis - experimental control - independent variable - sample A:
**Answer**
sample

*Question*
Q: Fish have a circulatory system with a two-chambered what? Read this paragraph and choose the correct option from the provided answers: Fish have a circulatory system with a two-chambered heart. Their digestive system is complete and includes several organs and glands. Jawed fish use their jaws and teeth to grind up food before passing it to the rest of the digestive tract. This allows them to consume larger prey. Choices: - brain - lung - stomach - heart A:
**Answer**
heart

*Question*
Q: What concentrates wave energy or disperses it? Read this paragraph and choose the correct option from the provided answers: Wave refraction either concentrates wave energy or disperses it. In quiet water areas, such as bays, wave energy is dispersed. This allows sand to be deposited. Land that sticks out into the water is eroded by the strong wave energy. The wave energy concentrates its power on the wave-cut cliff . Choices: - wave diffusion - a prism - wave reflection - wave refraction A:
**Answer**
wave refraction

*Question*
Q: What occurs when a cold air mass runs into a warm air mass? Read this paragraph and choose the correct option from the provided answers: A cold front occurs when a cold air mass runs into a warm air mass. This is shown in Figure below . The cold air mass moves faster than the warm air mass and lifts the warm air mass out of its way. As the warm air rises, its water vapor condenses. Clouds form, and precipitation falls. If the warm air is very humid, precipitation can be heavy. Temperature and pressure differences between the two air masses cause winds. Winds may be very strong along a cold front. Choices: - an occluded front - a stationary front - a snow day - a cold front A:
**Answer**
a cold front