1.   A twig bobs up and down in the water. It moves from its highest point down to its lowest point and back every 12 seconds. The distance between its highest and lowest points is 3.2 centimeters. Write a sine function that models the movement of the twig in relation to the equilibrium point.
    A. B.
    C. D.
    Hint

  2.   Suppose the equation models the number of liters of air in the lungs of a gorilla at t seconds. Use a graphing calculator to graph the function with Xmin = 0 and Xmax = 10.
    A. B.
    C. D.
    Hint

  3.   Suppose the equation models the number of liters of air in the lungs of a gorilla at t seconds. Find the amount of air in the lungs at t = 4.5 seconds.
    A. about 0.23 L B. about 0.19 L
    C. about 0.15 L D. about 0.17 L
    Hint

  4.   Suppose the equation   models a buoy bobbing up and down in the water. The equilibrium point is y = 0. Describe the location of the buoy when t = 0.
    A. equilibrium B. 6 units below equilibrium
    C. 0.5 unit above equilibrium D. 6 units above equilibrium
    Hint

  5.   Suppose the equation models a buoy bobbing up and down in the water. The equilibrium point is y = 0. Describe the location of the buoy when t = 7.
    A. 3 units above equilibrium B. 6 units below equilibrium
    C. 3 units below equilibrium D. 6 units above equilibrium
    Hint