The Sea Dragon, a pendulum ride at an amusement park, moves from its central position at rest according to the trigonometric function P(t)=−10sin(pi/3t), where t represents time, in seconds. How many seconds does it take the pendulum to complete one full cycle? A= 3
B= 5
C= 6
D= 10

Look at the figure below: triangle abc is a right triangle with angle abc equal to 90 degrees. the length of ac is 5 units and the length of ab is 4 units. d is a point above c. triangle adc is a right triangle with angle dac equal to 90 degrees and dc parallel to ab. what is the length, in units, of segment cd?