The answer is B) heat will flow from the water to the copper until they both reach the same temperature
A: Na3PO4 + MnCl2 > Mn3(PO4)2 + NaCl
I believe the answer is D. loess. The loess soil is a predominantly silt-sized sediment formed by accumulation of wind blown dust. This soil is highly porous, homogeneous, pale yellow and friable. One way of forming loess is from glaciers and that is why they contain glacially ground flour like clay and silt.
The answer for the first question would be water. It is the substance that is a compound since it is made up of different elements. For the second item, i think the best answer is phosphorus and nitrogen. They are the limiting nutrients. For the last item, the correct answer is reservoirs.