Finanical management problem

Sine Electronics is a midsized electronics manufacturer located in
Sichuan of China. In order to meet the rising demand for its products,
Sine Electronics is considering an investment in a new plant. The new
investment requires an initial outlay of $255,000,000, and it will generate
annual after-tax net cash flows of $18,000,000 in perpetuity. Sine
Electronics is a listed company which is financed by the following:

i 300,000 13.7% 15-year coupon bonds with par value of $1,000;
coupons are payable semi-annually, currently trading at 112 percent
of par.
ii 2,500,000 ordinary shares with par value of $1 and annual dividend
growth rate of 5%, currently trading at $84 each. The dividend for
last year was $6.6.

iii 4,000,000 shares of 10% preferred stock (with a $50 par value)
outstanding, currently selling for $40 per share.

iv Retained earnings of $50,000,000.

v Long-term bank loan of $150,000,000 at 8%.

a Suppose the corporate tax rate is 25%, calculate the weighted average
cost of capital of Sine Electronics.

b What does the answer of part a) mean? Is it appropriate for Sine
Electronics to use the answer of part a) as cost of capital for the new
investment project?