The current price of a bond is 100. The instantaneous rate of change or derivative of the price of the bond with respect to the yield rate is -700. The yield rate is an annual effective rate of 8%.

Calculate the Macaulay duration of the bond. Note: Recall that it is customary to drop the negative when computing volatility or modified duration.

a) 7.00

b) 7.49

c) 7.56

d) 7.69

e) 8.00