Answer:
Weight of debt = 2.43%
Step-by-step explanation:
A corporate bond usually has a par of $1,000; so a bond trading at a 108% of its par value means that the bond is trading at a market value of $1,080 ($1,000 par x 108%).
Now we can calculate the values of each investments.
Value of debt = $1080 market value x 7,000 bonds
Value of debt = $7,560,000
Value of common equity = 6,000,000 shares x $28 per share
Value of common equity = $168,000,000
Value of preferred equity = 5,000,000 shares x $27 per share
Value of preferred equity = $135,000,000
Now, in order to calculate weight of debt (WD) we need to divide it by total capital.
WD= Debt/(debt + common equity + preferred equity)

Weight of debt = 2.43%
Note: All values are rounded off to two decimal points