(10 POINTS What environmental change will take place when harmful substances get into the food and water supply of animals or plants?

A Climate change
B Increased predators
C Lack of food
D Pollution

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Magnesium is the limiting reactant in this experiment. calculate the theoretical yield of mgo for each trial. trial 1: trial 2: data mass of empty crucible with lid trial 1: 26.688 trial 2: 26.681 mass of mg metal, crucible, and lid trial 1: 26.994 trial: 2 26.985 mass of mgo, crucible, and lid trial 1: 27.188 trial 2: 27.180