the answer is a.
i say this is the answer because whenever you’re doing a scientific hypothesis you’re mostly observing and making assumptions.
Answer: By burning fossil fuels (coal, oil and natural gas) in industry, transport and the generation of electricity, which releases carbon dioxide. This is adding to the greenhouse effect, causing global warming.
Explanation: mark Brainliest
The correct answer is that mammals use a closed, double loop , four chambered heart as a circulatory system of the body.
The circulatory system of mammals is closed system that consists of four chambers, two articles and two ventricles. The deoxygenated blood comes into the heart from one loop and the oxygenated blood from other loop from the heart is circulated to the whole body. This is called as double circulation.
