The circulatory system has 4 chambers - 2 Atria and 2 ventricles. 2 Atria - the left atrium receives blood from the pulmonary (lung) circulation, and the right atrium receives blood from the venae cavae (venous circulation). The atria receive blood while relaxed (diastole), then contract (systole) to move blood to the ventricles.
2 Ventricles - two ventricles that operate in a double circulatory system: the right ventricle pumps blood into the pulmonary circulation to the lungs, and the left ventricle pumps blood into the systemic circulation through the aorta.
About 19.64 pounds of carbon dioxide are produced from burning a gallon of gasoline. On the other hand, 22.38 pounds of carbon dioxide are produced from burning a gallon of diesel. So, different fossil fuels will give different amounts of carbon dioxide to be released.
I’m going to say the answer is most likely X because memetic energy is energy being used at that moment. Because the coaster is going fastest at X we can assume that the answer is X