Answer:
WACC = 7.89%
Step-by-step explanation:
Lets find "cost of equity" first.
The formula is:

Which is basically the next year dividend divided by stock price summed with growth rate. So cost of equity is:

Now, "cost of debt":
Formula is:

Which is the yield to maturity times "1 - tax rate", so it will be:

WACC formula is:

Where
W_e is weight of equity, which is 45/(45+10) = 45/55 = 9/11
W_d is weight of debt, which is 10/(45+10) = 10/55 = 2/11
Now, wacc is:

In percentage, 0.0789 * 100 = 7.89%
WACC = 7.89%