The paranasal sinuses are . Group of answer choices air-filled spaces found within the frontal, maxilla, sphenoid, and ethmoid bones only air-filled spaces found within all bones of theskull not connected to the nasal cavity divided at the midline by the nasal septum

a unit of heredity that is transferred from a parent to offspring and is held to determine some characteristic of the offspring.

before, trains worked using the steam engine. thus, it uses heat so it is crucial to apply heat balance. the steam engine absorbs energy during the stage of boiling water. so, this is the endothermic reaction. when the steam is used to work the piston, it has to release this energy through running the train. the excess energy is released as an exhaust to the chimney. this is the exothermic process because it releases energy to the surroundings.