Where does the majority of drinking water come from in rural areas in north carolina? a. groundwater b. rivers c. oceans d. ponds

Calculate the molar mass of aluminum oxide (al2o3). express your answer to four significant figures.

3. how much energy in joules is required to evaporate .0005 kg of liquid ammonia to vapor at the same temperature? 4. how much energy ( in megajoules ) is given up by .75 kg of water at 0c when it freezes to form ice at 0c? 5. explain how heat works between and at critical temperatures?

Calculate the percent composition by mass of each element in al(oh)3. use at least three significant figures.