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Assume that the Earth is a sphere with a radius, $r$ , of $6.38 \\times10^3 km$.

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In this question use the formula for the surface area of a sphere.

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$A = 4\\pi r^2

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This should return a value of {s_area_act} on your calculator

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rounded to three significant figures this is {s_area}

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In standard form this is $5.12 \\times 10^8$

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You may have received credit for writing your (a) in standard form correctly.

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surface area of the Earth in km^2

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radius of the Earth in km

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a in standard form a x 10^k

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k in standard form a x 10^k

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Area rounded to 3.s.f.

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Second value of area which can be overwritten with answer to part (a)

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Calculate the surface area of the Earth in $km^2$

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Write your answer in part (a) in the form $a \\times 10^k$ where $1 \\leq a <10$.

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[[1]]$\\times 10$[[0]]

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