A 60-kg hiker wishes to climb a hill 1200 meters high. If he can generate a sustained average power of 500 Watts (realistic!), how long will it take him to climb the hill assuming he is 100% efficient? What would the answer be if he were only 10% efficient?

answer: the metamorphic rocks are formed when they are exposed to high pressure and high temperatures. this happens when one of the earth's plates comes in contact with the other plate by traveling in opposite directions, straight into each other or slipping under one another. the friction that is caused by this activity results in   melting of rocks and when it cools they are known as metamorphic rocks. this process needs a controlled amount of pressure and temperature otherwise it may turn into magma.

the answer is 12 as i may remember

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