How does thermal energy transfer when a room is heated by a furnace? ! a. hot air is absorbed by the objects in the room; cold air expands and rises. b. hot air is circulated through the room; the hot air rises, and cold air falls. c. hot air makes direct physical contact with the objects in the room and rises. d. hot air is transmitted by electromagnetic waves; the hot air rises and falls.

Which statement best describes a keystone species? o a. it has littlelmenetic variation. it has an extremely high population. 0 b. 0 c. it remains unaffected by all environmental changes. od. it has a strong influence on the ecosystem. 0 e. it's the first species to populate a new ecosystem.

Ineed a chemical reaction takes place in which erlergy is released. arrange the reaction's characteristics in order from start to finis lower energy of reactants higher energy of products higher energy of reactants transition state sd lower energy of products

Humans are believed to have evolved in coastal regions in east africa. the region had an abundant supply of fish for early humanoids to eat. when scientists analyze the fads gene they see an interesting pattern. people whose families have lived in this area of east africa for generation show a high level of diversity in alleles for the fads gene. conversely, people whose families had migrated inland a moderate distance from sources of fish showed a much lower diversity for fads gene alleles. additionally, the fads alleles found in people whose family has lived inland for generation are almost all gene alleles which produce fads proteins with a high level of function and activity. how do anthropologists explain this?