Is a apple tree a decomposer consumer or a producer?

What is a property of a double replacement reaction

Mary is conducting an experiment on how pollution affects plant growth. how can she ensure that her data are reliable?

Assuming complete dissociation of the solute, how many grams of kno3 must be added to 275 ml of water to produce a solution that freezes at -14.5 c? the freezing point for pure water is 0.0 c and k_f is equal to 1.86 c/m