What term is defined as mathematical equations based on rules of physics

Ageologist determines that a sample of a mineral cant be scratched by a steel nail but can be scratched by a masonry drill bit based on this information the sample mineral has to be softer than

Why are plants found at the beginning of a food web

30 points why do tornadoes happen more frequently in the summer? they require warm air. they form over large, warm bodies of water. they require dry air. they require dust which is present in the summer.