Which of the following statement is incorrect regarding cost of debt?

	a.	We need to take into account the floatation cost (commission) in calculating the cost of debt
	b.	The cost of debt is the coupon rate
	c.	When we calculate cost of debt, we usually focus on the cost of long-term debt or bonds
	d.	Cost of debt should be after-tax (as interest expense is tax deductible)