Which is the best definition of weathering? settling of Earth’s materials when water slows downb. swelling Earth’s materials as they soak up waterc. breaking up of rocks from wind, water, plants, or animalsd. transport of Earth’s materials by wind, water, or ice

15 ! come and answer! a(n) disease is caused by a pathogen and can spread among organisms. a infectious b noninfectious c toxic d contaminated

Svetlana and her mother are very similar. both have blonde hair, a love of scrapbooking, blue eyes, and a thin nose. which statement  most likely  describes svetlana’s traits? svetlana inherited her love of scrapbooking from her mother, but her blue eyes come from her environment.svetlana inherited her blue eyes from her mother, but her love of scrapbooking comes from her environment.svetlana inherited her thin nose from her mother, but her blonde hair comes from her environment.svetlana inherited her blonde hair from her mother, but her thin nose comes from her environment.

To answer this question, researchers studied populations of the dusky salamander (desmognathus ochrophaeus) living on different mountain ranges in the southern appalachian mountains. the researchers tested the reproductive isolation of pairs of salamander populations by leaving one male and one female together and later checking the females for the presence of sperm. four mating combinations were tested for each pair of populations (a and b)—two within the same population (female a with male a and female b with male b) and two between populations (female a with male b and female b with male a). the proportion of successful matings for each mating combination was measured. for example, when all the matings of a particular combination were successful, the researchers gave it a value of 1; when none of the matings were successful, they gave it a value of 0. then the researchers calculated an index of reproductive isolation that ranged from 0 (no isolation) to 2 (full isolation). the reproductive isolation value for two populations is the sum of the proportion of successful matings of each type within populations (aa + bb) minus the sum of the proportion of successful matings of each type between populations (ab + ba). the table provides data for the geographic distances and reproductive isolation values for 27 pairs of dusky salamander populations.