Below is the question with the answer. I am having a hard time understanding where some of the numbers are coming from (specifiaclly Rd). Any help is much appreciated!

Cowbell Corp. is a manufacturer of musical instruments. There are 52 million shares, each selling at $80 / share with an equity beta of 0.99. The risk-free rate is 5% and the market risk premium is 9%. There is $1.18 billion in outstanding debt (face value), paying a 9% s/a coupon for 15 years, which is currently quoted at 110% of par. Assuming a 40% tax rate, what is Cowbell Corp.s WACC?

E=52m x80=4.16 billion

D=1.18 x1.1=1.298 billion

V=5.458

w_E = E/V = 4.16 / 5.458 = .7622

R_E = R_f + b_E x (R_M R_f) = 5 + 0.99 x (9) = 13.91%

w_D = D/V = 1.298/ 5.458 = .2378

N = 30, PV = -1,000, PMT = 45, FV = 1,000; R_D = 3.9268%*2=7.8536%

R_D(1-T_C) = 7.8536 (1-.40) = 4.7122%

WACC = w_ER_E + w_DR_D(1-T_C) = .7622 (13.91%) + .2378 (4.7122%) = 11.72%