¿Cual es la estructura que realiza la digestión?

Experiment to investigate effect of medication on levels of stress in males and females. dependant variable?

The controlled use of fire by hominids: (a) limited the expansion of hominids into certain environments, such as dry grasslands. (b) decreased the amount of food energy available in the hominid diet. (c) contributed to geographical expansion and food production techniques in positive ways. (d) has been shown to contribute little to the digestive process of hominids.

Recently, there has been pressure to loosen clean air standards. use economic arguments to support or oppose this proposed action.