Use the first five terms of the trigonometric series to approximate the value of sin 14pi/18 to four decimal places. Then compare the approximation to the actual value.
a. -0.9609, -0.9659
b. -0.9568, -0.9659
c. -0.9649, -0.9659
d. 0.6432, 0.6428
Please select the best answer from the choices provided.