We have to calculate the total weight of the three samples. After that we have to choose the correct answer. Weight of those three samples is: 0.170 grams, 0.204 grams and 2.300 grams. We simply have to find the sum of those weights: 0.170 g + 0.204 g + 2.300 g = 2.674 g. Answer: C. 2.674 grams.