Read the scenario.
a group of scientists decides to conduct research to see whether access to a higher amount of a certain vitamin will improve the health of lab rats. they raise more than 500 rats, giving some the extra vitamin and some not, and keep track of how often the rats are sick and how long they live. the scientists’ findings are positive; the rats are healthier and live longer when they have access to the vitamin.
which option correctly identifies why this research was scientific?
a )the scientists researched a common situation and came to an interesting conclusion.
b )the scientists used proper ethical guidelines while performing their research.
c )the scientists’ question was testable, and their claim was based on evidence.
d )the research topic was generally important for people and could increase the quality of life for many.

a high pressure system is a dense air mass that is usually cooler and drier than the surrounding air. a low pressure system is a less dense air mass that is usually wetter and warmer than the surrounding air.

in general, areas that experience high atmospheric pressure also experience fair weather. low pressure systems can cause the formation of clouds and storms. air usually flows from areas of high pressure to areas of low pressure..

it's when something is going so fast it makes a loud noise, breaking the sound barrier, for example: a jet makes a loud noise, not only cause of the jet but because they reached a point where they went so fast that you can year the noise from various parts, kinda like a police car, lets say the car was going   so fast that you hear the siren of the cop car right next to you, but the car is probably a mile a way, it's cos the siren was next to you a few seconds if you understand me