In developed nations people have more fast food options which lead to cardiovascular disease. As well as screen time all day since this is one of the factors of cardiovascular disease. Undeveloped nations don't have fast-food or television to watch all day, since they play outside.
Kinetic energy is the energy that an object has because of its motion.
The answer to you question in true.
Http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0072434/
There is a website with some info. Hope it helps! :)
Answer:
I'm pretty sure the answer is natural selection.
Explanation:
Natural selection acts on phenotypic variations in populations.