12. Scientists once believed that Earth was the center of our Solar System. This is known as the Geocentric model. Which of the following is the most likely reason that this belief was revised?
A. Other scientists conducted simulations and collected data that led to them discarding this theory.
B. Astronomers observed that all the stars in the galaxy align.
C. New technology was used to collect evidence that refuted this theory. The theory was revised based on
the new information that was collected.
D. Scientists discovered that the Earth was not flat therefore the planet could not be at the center of our
Solar System.

c. the initial amount of money placed in the savings account

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.

the correct answer is 2 and 4

blood enters the heart through two large veins, the inferior and superior vena cava, emptying oxygen-poor blood from the body into the right atrium of the heart. as the ventricle contracts, blood leaves the heart through the pulmonic valve, into the pulmonary artery and to the lungs where it is oxygenated.