Question 1160909
A buoy rises and falls as it rides the waves. The equation h(t)= sin(36t) models the displacement of the buoy, h(t), in metres at t seconds. a) Determine the period of the function. 
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The period of sin(t) is 2pi
Period of sin(36t) is 2pi/36 = pi/18 seconds
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b) What is the displacement at 30 s?
h(30) = sin(36*30) = 0
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 c) What is the displacement at 12 s?
h(12) = sin(36*12) =~ 0.951 meters
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 d) At what time, to the nearest tenth of a second, does the displacement first reach 0.7 m.
h(t) = sin(36t) = 0.7
36t =~ 44.42
t =~ 1.2 seconds