Question 1078498
a)  T^2 = k * d^3, where k is the constant of proportionality
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b)  1^2 = k * 150^3
k = (1 / 3375000)
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c.  T^2 = (1 / 3375000) * (30 * 150)^3
T^2 = 27000
T = 164.3168
From NASA publication Neptune's period is 165 earth years
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d.  (T(Y) / T(X)) = (2 * d(X)) / d(X))  = 2 = 200% = twice as long
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