Question

up, up, and away! hot - air balloons fascinate, amaze, and delight people of all ages. these colorful creations seem to float effortlessly across a clear blue sky. yet they are strong enough to support multiple passengers and equipment. how is that possible? it all comes down to one thing—science. hot - air balloons are based on a single concept: warm air rises and cool air falls. this is because cold air is denser than warm air. density is defined as the ratio of mass to volume; it tells us how many molecules occupy a space at one time. the more molecules there are in a given volume, the denser the substance. the fewer molecules there are, the less dense the substance is. warm air, in which the molecules are farther apart, is less dense than cold air. for liquids and gases, a substance that has greater density sinks to the bottom. what does the word detect mean as it is used in paragraph 6? 1. absorb 2. change 3. eliminate 4. find

Explanation:

In the context of the paragraph about hot - air balloons and density concepts, the word "detect" means "find". The text is discussing how science helps in understanding the principles behind hot - air balloons, and "find" makes the most sense in the context of what science does in relation to these phenomena.

Answer:

1. find