The principal gas in the biogas produced in a landfill is

Biogas is composed mostly of methane (CH4), the same compound in natural gas, and carbon dioxide (CO2).

Explanation:

economic impact of malaria is estimated to cost africa $12 billion every year. this figure factors in costs of health care, absenteeism, days lost in education, decreased productivity due to brain damage from cerebral malaria, and loss of investment and tourism.