Answer:

Explanation:
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In this case, when we have a gas that is undergoing a change in both pressure and temperature, we utilize the Gay-Lussac's equation as shown below:

Thus, since we are given the initial pressure and temperature and the final temperature, we can compute the final pressure as shown below:

So we plug in, by making sure the temperatures are in kelvins, to obtain:

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Greater density means to greater mass and greater mass to more gravity on the body
Take 56 mL and subtract the original volume of 50 mL and that will give you the volume of the rock, which is 6mL.