A hiatal hernia or failure of the lower esophageal (cardiac) sphincter to close causes the stomach contents to back up into the esophagus. This causes the esophageal wall to have a burning sensation (heartburn) and, in serious cases, bleeding. What causes the burning sensation and bleeding to occur

The phlogiston theory in the 17th century attempted to explain burning. the theory stated that combustable objects contained a material called phlogiston, a substance without mass, color, odor, etc. after objects burned, the objects were dephlogistonated and were then in their true form. the phlogiston theory was accepted until the 18th century, when lavoisier proved that combustion requires a gas that has mass. phlogiston is considered a) to be scientific knowledge b) not to be scientific knowledge c) to be proven by scientific method d) to be accepted in the modern scientific community

Which of the following is an effect of the uneven heating of the earth by the sun? a sea breeze a land breeze a convection current all of the above

Which of the following types of rock would most likely contain a fossil? slate granite lava rock limestone