The biggest concern about carbon dioxide change in earth’s atmosphere is

Plants need carbon dioxide to make oxygen that we breathe in. Humans inhale oxygen to create carbon dioxide, so lessening the amount of carbon dioxide would cause the human population to decrease more and more over time

the roman republic began to expand when rome fought the punic wars and defeated carthage. the punic wars refer to the series of 3 wars fought among rome and carthage, before it ended in carthage's defeat.