Which uses combustion to transfer thermal energy to warm a building? heat engine furnace refrigeration unit heat pump

Can a trait be both polygenic and have multiple alleles? explain why or why not.

This is collection of data made by comparing objects in standard units. in science, the units are metric.

Which of these would most likely be a stimulus that would cause the body to initiate feedback mechanisms a.) normal body temperature in an arctic environment b.) normal boy temperature in a tropical environment c.)light physical activity d.)low blood sugar