An air-track glider attached to a spring oscillates with a period of 1.50s. At t=0s the glider is 5.40cm left of the equilibrium position and moving to the right at 39.2cm/s.
a. What is the phase constant?
b. What is the phase at t=0.5s?
c. What is the phase at t=1.0s?
d. What is the phase at t=1.5s?
Express your answer to three significant figures and include the appropriate units.