A weight attached to a spring is at its lowest point, 9 inches below equilibrium, at time t = 0 seconds. When the weight it released, it oscillates and returns to its original position at t = 3 seconds. Which of the following equations models the distance, d, of the weight from its equilibrium after t seconds?a. d=-9cos(pi/3)tb. d=-9cos(2pi/3)tc. d=-3cos(pi/9)td. d=-3cos(2pi/9)t

The equation which models the distance (d) of the weight from its equilibrium after time (t) is equal to d = -9cos(2π/3)t.What is the period of a cosine function?The period of a cosine function simply means the total length (distance) of the interval of values on the x-axis over which a graph lies and it's repeated. Since the weight attached is at its lowest point at time (t = 0), therefore, the amplitude of equation will be negative nine (-9)For the angular velocity at time period (t = 3s), we have:ω = 2π/Tω = 2π/3Mathematically, the standard equation of a cosine function is given by:y = Acos(ω)tSubstituting the given parameters into the formula, we have;d = -9cos(2π/3)t.Read more on cosine function here: