An ecosystem is all the populations of organisms that live together and A.
the food that they take in as energy.
B.
the organisms that generate energy from sunlight.
C.
the microorganisms that depend on them.
D.
the physical factors with which they interact.

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What are the three major branches of natural science? • earth and space science, life science, physical science •earth and space science, physical science, chemistry •physical science, life science, chemistry •life science, chemistry, physics

7. using your knowledge of colligative properties explain whether sodium chloride or calcium chloride would be a more effective substance to melt the ice on a slick sidewalk. use 3 – 4 sentences in your explanation. 8. when a 2.5 mol of sugar (c12h22o11) are added to a certain amount of water the boiling point is raised by 1 celsius degree. if 2.5 mol of aluminum nitrate is added to the same amount of water, by how much will the boiling point be changed? show all calculations leading to your answer or use 3 – 4 sentences to explain your answer. 9. if 5.40 kcal of heat is added to 1.00 kg of water at 100⁰c, how much steam at 100⁰c is produced? show all calculations leading to an answer. 10. the freezing of water at 0⁰c can be represented as follows: h2o (l) ↔ h2o(s) the density of liquid water is 1.00 g/cm3. the density of ice is 0.92 g/cm3. in 3 – 4 sentences explain why applying pressure causes ice to melt.

What substance has a mass of 9.5g and volume of 2.1cm^3