The action force is you sitting on the chair and the reaction force is the gravity on the chair that is caused by you sitting on the chair
The right answer for the question that is being asked and shown above is that: "where plants, animals, the landscape and the climate are all independent of each other." An ecosystem is a geographical area <span>where plants, animals, the landscape and the climate are all independent of each other.</span>
Answer:

Explanation:
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In this case, since no information about the reacting hydrogen is given, we can assume that it completely react with the 28.0 g of acetylene to yield ethane. In such a way, via the 1:1 mole ratio between acetylene (molar mass = 26 g/mol) and ethane (molar mass = 30 g/mol), we compute the yielded grams, or the theoretical yield of ethane as shown below:

Hence, by knowing that the percent yield is computed via the actual yield (24.5 g) over the theoretical yield, we obtain:

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