The brain structure that controls unconscious but essential functions such as breathing and circulation is the

The correct answer is medulla oblongata.

Medulla oblongata is the part of the central nervous system. It is the structure which continiues to spinal cord and represents the lowest part of the brainstem. Function of medulla oblongata is to control involuntary, autonomic functions. It contains centers for the heart and lungs, thus it regulates functions of breathing, heart rate and blood pressure.

that would be called plucking : )

explanation:

''plucking, also referred to as quarrying, is a glacial phenomenon that is responsible for the erosion and transportation of individual pieces of bedrock, especially large "joint blocks". as a glacier moves down a valley, friction causes the basal ice of the glacier to melt and infiltrate joints (cracks) in the bedrock."

just finished the test, the answer is d, greg is the least cost-effective because he charges the most for the project