What is it called when certain species have evolved such intimate symbiotic relationships that individuals of either species cannot survive without one another? a) obligate
b) mutualistic
c) parasitic
d) facultative

of those who start drinking before they're 15 will develop alcohol dependence

explanation:

for  example, forests have higher evapotranspiration than other ecosystems,  such  as grasslands, because of their deeper roots and greater leaf area. thus forests have a net moistening effect on the atmosphere and become a moisture source for downwind ecosystems.

i think its the first one

sulfur dioxide

explanation: acid rain is caused by a chemical reaction that begins when compounds like sulfur dioxide and nitrogen oxides are released into the air. these substances can rise very high into the atmosphere, where they mix and react with water, oxygen, and other chemicals to form more acidic pollutants, known as acid rain.